I am always very impressed by what you are able to recover, the cold weather must help keep things fresh. It seems to me though that as a solution it does not scale well. Have you considered trying to get these supermarkets to use biodegradable or consumable packaging? Then they could compost everything or better yet use it as hog food. Then nothing would go to waste. Humans have always produced a lot more food than we eat but we never considered the excess to be waste, it was animal feed or compost.