Behavioural Economics

By Uma Karmarkar

Several cities, and even countries, have taken steps to ban retail use of plastic bags, or to require businesses to charge for giving them out… As concerns about climate change and resource availability become more central in public discourse, using reusable grocery bags has been strongly promoted as an environmentally and socially conscious virtue.

In parallel, firms have joined policymakers in using a variety of initiatives to reduce the use of plastic bags. However, little is known about how adopting reusable bags might alter consumers’ in-store behaviour.

Using scanner panel data from a single location of a major grocery chain, and controlling for consumer heterogeneity, we demonstrate that bringing your own bags increases your purchases of environmentally conscious and indulgent (hedonic) items.

Supporting these effects, we use experimental methods to demonstrate that participants who imagined shopping with their own bags are more likely to spontaneously consider purchasing chips or dessert items, and indicate relatively higher willingness to pay for foods in these categories, as well as for organic foods.

Also, we show that the impact on organic and indulgent items is dissociable in a manner dependent on the consumers’ motivation for bringing bags. The findings have implications for decisions related to product pricing, placement and assortment, and store layout.

From "How Bringing your Own Shopping Bags Leads to Treating Yourself, and the Environment"