Yes, there is a downside for people who tend to do "impulse" shopping. With coupons, the whole idea is to get you to buy a particular brand instead of a competitor's brand. So, if you usually buy generic corn but decide to use a coupon for 50 cents off a name-brand product priced much higher, you're losing money by using a coupon. But, once you learn the art of using coupons strategically, it's simple to avoid this pitfall and save money on every trip to the grocery store or any other store.