Went to a pub Friday night for beer and food - bill £34-80, offered the machine but paid by cash in the form of two £20's, given £14-80 change...
Bar maid said it was the first time that anyone had paid that much by cash for ages.
I did point out that what she gave me was wrong (I knew it was wrong before I had the money in my hand as she pulled a tenner out of the till rather than a fiver) and she had to look twice before realising what she had done; then she blamed the till for giving the wrong info.