Scenario
You pay for a restaurant meal with your credit card. When the waiter returns, you sign the receipt and slip the card back into your wallet, same as always. But the next time you use the credit card, it is declined. When you examine the card, you realize that it is not your credit card, but rather a similar-looking card with someone else's name on it.
How It Happens
Unscrupulous restaurant and retail employees occasionally carry a few old credit cards, perhaps ones stolen from previous customers, that have been canceled by their owners. When a customer pays with a card that is similar in appearance, the scammer pockets the new card and substitutes the old one. If the victim fails to notice, the thief goes on a shopping spree.
Self Defense
Always double-check that the credit card returned to you really is your card.