I had an experience at an American restaurant recently where the waiter started asking very detailed questions about where we were from, etc. When we said we were living in Europe he got a deer in headlights look and asked if we had ever lived in the US. I wondered whether he might be worried that he wasn't going to get a tip.

Any Europeans ever experience this? I'm still not sure if I was right or not, but his mood definitely lightened when I said yes, we've lived in the US.