Those little slips of paper -- coupons -- are real money and someone has to pay for the discount you just received. It could be the store, the manufacturer or someone else. You may have paid for it before you left the house.
The world of coupons is complicated and there are lots of ways scammers can creep in. The average person is the most common way. It happens when we buy coupons online or try to print our own.
Then there is the coupon processing system that provides another entry point.
We'll explain it all to you so that you're not standing at a cash register, getting the hairy eyeball from a manager who believes you're trying to use fake coupons.