With Credit Cards they charge the places you buy stuff a fee. Can be anywhere from 0% to 10% on whatever you buy. This is where the CC companies make their money, assuming you pay off your CC every month (or you pay interest).
To get you to use your CC more these companies are now offering you a percentage of the fee they take from the store. So let’s say they charge 5% to the store to use their CC machine, and give you back 2%. On a $100 charge the store gets $95, you get $2 and the CC company gets $3.
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