Hoooo boy! Something else to watch out for...
I’ve been given the wrong credit card back multiple times. Fortunately I’ve been able to retrieve mine without a problem.
Person gets the wrong card handed back to her? That's a "mixup".
Person just sticks the card back in their wallet and walks out with it? I could see that happening. Mixup.
Person quickly walks across the street to the nearest mall and starts running up a tab on it?? Fraud. And pretty stupid to boot, especially since they just likely swapped cards, and the real cardholder has their name.