This one is actually from a coworker of mine from a few days ago.
CW will be coworker and OM will be old man.
This old man comes in to pay his bill, nothing out of the ordinary. Of course, he wants to use a check like every old person and refuses to use our payment machine.
My coworker helps him out, takes the payment, and like we're supposed to, voids the check away the end of the transaction.
OM- What are you doing?
OM- You just destroyed my check.
CW- I just voided the check so I can hand it back to you for your records.
OM- No you destroyed it. The other store doesn't do that. Since you destroyed the check I can't use it again. You made me lose a check.
CW- Sir that's how it always is. We put the check number in the system so you shouldn't be able to use it again.
OM- No I've used those checks again. You destroyed my check.
At this point my coworker just gave up and apologized and the customer left the store. We all started wondering how long it was going to be before they blacklist him from using checks after his bank rejects payment for duplicate checks.