I assumed that the grocers would want to offer bags. Making it more easy to drop in and buy something is going to be significantly more money than the cost of bags per a customer.
Maybe they want you to spend an extra 10 cents every time you drop in and buy something? And they get to be pro environment. Win win.
Maybe they want you to spend an extra 10 cents every time you drop in and buy something? And they get to be pro environment. Win win.