It's in the bag? The effect of plastic carryout bag bans on where and what people purchase to eat
研究加州塑料袋禁令如何影响消费者购买食品的地点，发现禁令导致受监管超市的食品销售额下降1.8%，消费者外出就餐支出份额增加1.9个百分点，部分消费者通过跨境购物或转向餐馆规避禁令。
Abstract This paper examines how banning the use of plastic carryout bags at grocery stores affects where and what people purchase to eat. Using quasi‐random variation in local bag ban adoption across California and two data sources (retail scanner data and consumer survey data), I show that banning plastic carryout bags shifted some food sales away from regulated grocery stores toward unregulated grocery stores and restaurants. Specifically, I find that bag bans cause a 1.8% decline in food‐at‐home sales and a 1.9 percentage point increase in consumers' food‐away‐from‐home expenditure share. The decline in food‐at‐home sales is larger in jurisdictions more likely to experience cross‐border shopping, whereas the increase in food‐away‐from‐home expenditures is larger farther from jurisdiction borders. Together these results suggest that a small share of consumers find a way to bypass the bag bans—either by cross‐border shopping if near a border or by shifting to restaurants if not near a border. Heterogeneity analyses reveal the policy effects are strongest for those with higher incomes, those under 65 years, and those with young children, suggesting both income effects and time constraints as mechanisms behind the behavioral change. By quantifying consumer avoidance behaviors, these results enable policymakers to more accurately measure the impacts of their regulations and to understand the potential trade‐offs between their environmental and public health objectives.