When Do Consumers Choose Greener Groceries? The role of situational factors

Blog post based on the master's thesis of Martina Sabba

Consumers are increasingly aware of the environmental impact of their consumption. Many express a willingness to make more sustainable choices, and food consumption is often cited as a key domain in which individual behaviour can contribute to climate goals. In the European Union, food-related consumption accounts for roughly 22% of household greenhouse gas emissions, making grocery purchases a meaningful lever for environmental impact (European Commission, 2023; JRC, 2024).

Yet despite consumers’ awareness, sustainable intentions often fail to translate into action at the point of purchase. This attitude–behaviour gap has traditionally been attributed to limited attention to sustainability cues, such as eco-labels or certifications, which are frequently overshadowed by attributes such as price, taste, and brand reputation (Vermeir & Verbeke, 2006; Grunert et al., 2014).

Less studied (as a potential driver of the attitude-behaviour gap) is the role of the shopping context. Consumers do not make grocery decisions in a vacuum: they shop under time pressure, within specific store environments, and with different goals in mind. These situational factors shape how decisions are made and which product attributes receive attention. Understanding sustainable consumption, therefore, requires moving beyond attitudes alone and examining how everyday shopping contexts influence outcomes.

Sustainability in Grocery Shopping: Evidence from Danish Beverage Purchases

To explore this question,  household-level grocery purchase data from Denmark were analysed, collected via digital receipts from the Spenderlog app, between 2023 and 2025. The analysis focuses on the beverage category, a frequently purchased, relatively low-involvement product group that has received limited attention in sustainability research, despite its environmental relevance.

Using external life-cycle assessment data, product-level CO₂ emission estimates for packaging and transport were constructed and aggregated into basket-level measures of relative CO₂ intensity. Rather than focusing on total emissions, examining how emission-efficient consumers’ choices were on average allowed to isolate differences driven by choice rather than by volume alone. The analysis applies mixed-effects models with a Mundlak specification to separate situational effects from stable differences across consumers and stores.

This approach enables asking a practical question: under which shopping conditions do consumers purchase more or less emission-efficient grocery baskets?

Shopping missions matter more than attitudes

One situational factor stands out clearly: the shopping mission.

Grocery trips differ in purpose. Some are small, time-pressured “fill-in” trips aimed at replacing a few missing items and characterised by time-constrained, habitual behaviour, encouraging heuristic decision-making. Others are larger “stock-up” trips, typically more planned and involving broader category coverage (Kahn & Schmittlein, 1989; Zhuang et al., 2006).

Results show that stock-up trips are consistently associated with lower relative CO₂ intensity than fill-in trips. In other words, when consumers shop to stock up, their purchased beverage products tend to be more emission-efficient than when they shop to fill in.

At first glance, this might suggest that stock-up shoppers are more environmentally conscious. Stock-up trips are generally less time-pressured and allow for more deliberate decision-making (White et al., 2019), allowing for more thoughtful processing of sustainability cues. However, a closer examination also points to a more structural explanation. Stock-up trips involve larger quantities, bulk formats, and consolidated purchases, which benefit from packaging and transport efficiencies. Prior life-cycle research shows that such efficiencies can substantially reduce emissions per unit (Pasqualino et al., 2010). Both cognitive and structural explanations go hand in hand in driving more sustainable purchases during stock-up trips.

Do store formats shape sustainable outcomes? Less than expected

Retail environments differ widely. Supermarkets, discounters, and convenience stores vary in assortment breadth, price positioning, and shopping experience. These differences are often assumed to influence sustainable behaviour, with more “premium” environments expected to foster greener choices, and more “value-focused” stores increasing the salience of price – leading to less involved consideration of sustainability cues.

Surprisingly, once we account for stable differences between consumers, store format does not exert a systematic effect on the emission efficiency of beverage baskets. Supermarkets, discounters, and convenience stores do not differ meaningfully in within-category CO₂ intensity once consumer heterogeneity is controlled for.

This finding challenges a common assumption in sustainability discourse. While store formats clearly influence what consumers buy, including category mix, volumes, and price levels, they appear to play a much more limited role in shaping how emission-efficient choices are within a given category.

In practice, this suggests that much of the observed association between store format and sustainability may reflect who shops where, rather than direct causal effects of the retail environment itself.

Promotional intensity reshapes sustainable choice across store formats

Promotions are often seen as detrimental to sustainable consumption, as they increase price salience and encourage deal-seeking behaviour at the expense of credence attributes such as environmental impact (Chandon et al., 2000).

Our findings reveal a more nuanced picture. Promotion intensity interacts with store format in shaping sustainability outcomes.

• In convenience stores, higher promotion intensity is associated with lower relative CO₂ intensity.

• In discounters, higher promotion intensity is associated with higher CO₂ intensity.

• In supermarkets, no systematic relationship emerges.

These differences highlight that promotions do not operate uniformly across retail contexts. In time-driven environments like convenience stores, promotions may act as a “windfall” – an unexpected positive surprise that enables consumers to choose more emission-efficient options with the money they just saved. In highly price-oriented environments such as discounters, promotions may instead only amplify price salience even further, reinforcing cost-driven product choices that are less emission-efficient.

Rather than uniformly undermining sustainability, promotions thus appear to reconfigure decision priorities, with effects that depend strongly on retail context.

Stable consumer differences outweigh situational nudges

Another important insight concerns category importance, measured as the share of a consumer’s grocery budget devoted to beverages.

Consumers for whom beverages represent a consistently important category tend to purchase more emission-efficient baskets across trips. Crucially, this effect reflects stable differences between consumers, rather than short-term fluctuations in involvement during specific shopping trips.

This finding suggests that sustainable outcomes are driven less by momentary attention shifts and more by enduring shopping styles and habits. While situational factors such as shopping mission shape outcomes, persistent consumer characteristics play a larger role in explaining why some baskets are consistently greener than others.

Implications for retailers and policymakers

Taken together, the results point to an important conclusion: sustainability outcomes in grocery shopping are shaped by an interaction between cognitive processes and structural shopping conditions.

Greener outcomes often emerge not solely because consumers consciously choose “green” products, but because certain shopping contexts and purchase structures, such as stock-up trips, bulk formats, and consolidated purchases, create conditions that make emission-efficient choices more likely. These structural influence both the opportunities consumers face to “go greener” and the cognitive capacity they have available for evaluating sustainability-related attributes.

For retailers, this implies that sustainability strategies should not rely exclusively on informational cues or appeals to consumer values. While cognitive engagement and awareness remain relevant, their impact is constrained by the shopping context. Structural interventions, such as encouraging consolidated purchasing, aligning promotions with lower-emission options, and reducing packaging intensity, can support more sustainable outcomes by shaping the decision environment in which consumers make their choices.

For policymakers, the findings highlight the limits of interventions that focus primarily on attitudes and intentions. Awareness campaigns may increase concern, but their behavioural impact is likely to remain modest unless supported by changes in the retail environment that reduce time pressure, price salience, or decision complexity. Policies that influence retail architecture, assortment design, or packaging standards may therefore be more effective than those aimed solely at activating sustainability concerns at the point of purchase.

A reframing of sustainable consumption

Sustainable grocery shopping is often framed as a moral or motivational challenge: consumers are assumed to act unsustainably because they lack concern, information, or commitment. The present findings suggest a complementary perspective.

Sustainability outcomes rely on what consumers value, but just as much on if and when they can act on it. Shopping missions, time limits, and retail settings influence how much consumers can focus on sustainability. During routine or hurried shopping, structural constraints often prevent reflective decision-making, even for environmentally conscious consumers.

Understanding sustainable consumption, therefore, requires greater attention to the structure of everyday purchasing contexts and to the cognitive conditions they create. Greener behaviour does not necessarily begin with greener intentions; it often begins with shopping environments that allow those intentions to matter.

Selected references

• Chandon, P., Wansink, B., & Laurent, G. (2000). A benefit congruency framework of sales promotion effectiveness. Journal of marketing, 64(4), 65-81. https://doi.org/10.1509/jmkg.64.4.65.18071 

• European Commission. (2023). Special Eurobarometer 538: Attitudes of Europeans towards the environment. Publications Office of the European Union. https://europa.eu/eurobarometer

• Grunert, K. G., Hieke, S., & Wills, J. (2014). Sustainability labels on food products: Consumer motivation, understanding and use. Food Policy, 44, 177–189. https://doi.org/10.1016/j.foodpol.2013.12.001

• Kahn, B. E., & Schmittlein, D. C. (1989). Shopping trip behavior: An empirical investigation. Marketing Letters, 1(1), 55–69. https://doi.org/10.1007/BF00436149

• Pasqualino, J., Meneses, M., & Castells, F. (2010). The carbon footprint and energy consumption of beverage packaging selection and disposal. Journal of Food Engineering, 103(4), 357–365. https://doi.org/10.1016/j.jfoodeng.2010.11.005

• Vermeir, I., & Verbeke, W. (2006). Sustainable food consumption: Exploring the consumer attitude–behavioral intention gap. Journal of Agricultural and Environmental Ethics, 19(2), 169–194. https://doi.org/10.1007/s10806-005-5485-3 

• White, K., Habib, R., & Hardisty, D. J. (2019). How to SHIFT consumer behaviors to be more sustainable: A literature review and guiding framework. Journal of Marketing, 83(3), 22–49. https://doi.org/10.1177/0022242919825649 

• Zhuang, G., Tsang, A. S., Zhou, N., Li, F., & Nicholls, J. (2006). Impacts of situational factors on buying decisions in shopping malls. European Journal of Marketing, 40(1/2), 17–43. https://doi.org/10.1108/03090560610637293