re: What's the most you've ever paid/seen someone pay with change?

One time while standing in line to pay a bill at a restaurant, I noticed the person in front of me paying in change. Looking closer, I realized it was likely a stolen or grandpa's (or both) coin collection. There were numerous obvious real silver halves, quarters, dimes, etc.; and someone had even broken proof sets out of their plastic cases and was spending them at face value.

The cashier was still taking the coins off the counter when I walked up. There was a shiny coin off to the side that I picked up and said "I'll trade you." and handed her a regular nickel from my pocket. The coin I took was a 1976 frosted proof nickel.