I think this is a sign of a regional monopoly, like when the cable company gives you a six hour window for a service call. It probably isn't worth the small am

I think this is a sign of a regional monopoly, like when the cable company gives you a six hour window for a service call. It probably isn't worth the small amount of theft you stop to alienate customers (otherwise grocers in Los Angeles would do it) by checking receipts. But if you are the only affordable store in town you don't really have to worry about alienating customers.