I remember specifically handing cashier a $10 Bill. The item was $7.75. Register was broken. After about 2 minutes He gave me 9.25. I asked how he got that. He said “75 and 25 are 1. 10 minus 1 is 9. So 9.25”. He then gave me a look like I was a dumbass for not knowing that. I said “thank you”...bonehead.
I don’t use cards of any kind. After being hacked 4 times one yr I cancelled my card and pay cash for everything. Course I write checks for utility bills etc.