Social norm perceptions are implicit rules of conduct that describe what is normal and acceptable behavior. Changing social norm perceptions through textual and physical social norm communications can be a promising approach to changing behavior. Past studies, however, primarily relied on controlled (lab) experiments, leaving it unanswered to what extent these norm communications relate to social norm perceptions in a complex context. The present study addresses this issue for meat substitute purchases: to what extent can a social norm intervention in real-world supermarkets stimulate meat substitute purchases, and to what extent do social norm perceptions favoring meat substitute purchases mediate this relationship? A 13-week social norm intervention was implemented in three experimental supermarkets (with n = 3 matched control stores). Social norms were communicated textually on stickers and banners in the meat aisle and physically through increased shelf space for meat substitutes and island shelves with legumes. A total of N = 639 participants (n = 327 control) completed a survey upon exiting the supermarket, measuring social norm perceptions and collecting receipts to measure meat substitute purchases in grams. Results show that the likelihood of meat substitute purchases was OR = 3.6 times larger in intervention supermarkets (B = 1.28, SE = 0.512, z = 2.50, p = .012) than in control stores. However, their norm perceptions did not differ between intervention and control stores. In sum, a social normative intervention in a complex surrounding may impact purchasing behavior, but the mechanism driving this remains to be identified.
Wolfswinkel et al. (Fri,) studied this question.