Title: BYOB
Description: As concerns about pollution and climate change have become more central in public discourse, shopping with reusable grocery bags has been strongly promoted as environmentally and socially conscious. In parallel, firms have joined policy makers in using a variety of initiatives to reduce the use of plastic bags. However, little is known about how these initiatives might alter consumers' in-store behavior. Using scanner panel data from a single California location of a major grocery chain, and completely controlling for consumer heterogeneity, we demonstrate that bringing your own bags simultaneously increases purchases of environmentally friendly as well as indulgent (hedonic) items. We use experimental methods to further demonstrate causality and to consider the effects of potential moderators. These findings have implications for decisions related to product pricing, placement and assortment, store layout, and the choice of strategies to increase the use of reusable bags.