Turning up to a restaurant where you have made a reservation, only to find that it is almost completely empty. I vacillate between saying “I reserved a table for two at 8pm”, which seems silly and otiose, and saying “Do you have a table for two?”, which makes be feel like they are going to think I’m a flake when they look in their reservations book at the end of the evening and see that I never claimed my reservation. In the end, of course, I do the worse thing possible and say something like “I can see that it doesn’t really matter, but I made a reservation for two at 8pm”, which does the double duty of being basically unnecessary and emphasising to the owner quite how empty their restaurant is.