With most credit cards, your entire purchase history (sometimes including item-level data) is for sale to data brokers and advertising companies. It's a high price for that 1-3% cash back.
Some cards (e.g. Amazon Store Card) get you relatively high rewards at a specific vendor (Amazon). I predict there are special deals in place with the banks/transaction processors involved that make these rewards more possible.
Not sure why people down vote it? then again who cares.