Never encountered a store that discounts like you say, but accept that different folks mights shop in different kinds of places. WalMart, Costco, Home Depot and Kroger pretty much cover it for me. Even ate out last night - yup, they take credit cards.
Very common with small business. Many independent auto repair shops will give a discount and not charge tax. The repair invoice won't be found in a computer, though. A printed copy is placed in a special file before the computer record is deleted.