I witnessed a pretty crusty-ish return the other day in a different store. I was waiting in line to make a return myself, and could overhear what was going on at the tills as I waited. From what I could gather the basic gist was:
A couple in their mid-sixties had bought a pair of slippers before Christmas, and then carried on browsing in the store for a while afterwards.
When they got home they decided that they didn't want the slippers, but couldn't find their receipt. They went back to the area they were browsing after their purchase the next day, found a receipt on the floor for a different item, and were trying to return the slippers with that!
The poor girl working the returns desk kept trying to explain that, without the receipt, they could only have vouchers for the value of the item in the sale (50% off).
The old guy just kept repeating "But we HAVE a receipt!"
She couldn't get through to them that it had to be a receipt for the actual item being returned.
No way you can live to that age without making a return in your life, to not know how it works. Eventually they "graciously" agreed to accept 50% in vouchers and left.