That is so true. The big box stores encourage over-consumption, with the sale of quantities large enough to provide for a football team whether or not you actually require that much. I try to do the twice a week thing as well with food. Buying in manageable portions totally helps you control your weight as well. And cutting back on the purchase of processed foodstuffs as well.
I support those who appreciate my business. Some of the local stores around here, they are not always kind to their customers. The big brand stores, usually I don't blame them if their employee acts a fool, so I go by their polices. But a local store it's usually the owner or a relative, so if they are rude, I will shop elsewhere. However mostly the good owners outweigh the bad.