WonderFoods supermarket implemented a program to reduce plastic bag usage by providing reusable green bags and placing recycling cages in their parking lots. Customers are given green bags during their shopping and can return extra bags to the cages. This eliminates the need for plastic bags and has reduced plastic bag consumption by 80% while promoting the supermarket's eco-friendly image. The initial costs were covered by the supermarket's marketing budget and they expect to recoup their investment within a year.