Reducing Plastic Bag Use through Prosocial Incentives

While excessive plastic use has severe ecological consequences, the distant nature of these consequences may limit their effect on individual plastic use behavior. One possibility to address this problem is to link plastic use behavior to more direct consequences. Pro-environmental behavior researchers adopting this approach typically try to change people’s behavior by providing them with monetary incentives. Here, we pursued an alternative strategy by linking pro-environmental behavior to prosocial incentives. Takeaway customers of a fast food restaurant were informed that, for every unused plastic bag, a small donation would be made to a charitable organization. In comparison to baseline and control conditions, the likelihood of using a restaurant-provided plastic bag was more than halved when plastic-bag refusal led to such prosocial incentives. In addition, we tested whether the effectiveness of prosocial incentives depended on their size and on the type of organization (prosocial vs. environmental) receiving the incentive. While these latter analyses revealed some promising trends, they did not allow for definitive conclusions about the effect of these parameters. Hence, while our field experiment provides support for the general effectiveness of prosocial incentives, more research is needed to determine which prosocial incentives are most effective in shaping plastic bag use and other environmentally relevant behaviors.