I believe that Discover only pays 5% on whatever category is chosen for that month (or quarter), not on every purchase. There is American Express Blue Cash Everyday that pays 1% for purchases, 2% for gas stations and dept. stores, and 3% at supermarkets. This is a no fee card. Chase Freedom gives the 5% on selected categories and 1% for everything else. It's tough to get a good % of cash back unless you pay an annual fee.