Washroom Attendant
I did not ask you to live in the bathroom like a sink troll. I actually find it unnerving that you were just sitting there, listening to me pee, waiting for me to emerge. Hand towel ever so unenthusiastically at the ready.
The tip for such a necessary service? A big old smile. Don't spend it all in one place.
If I knew I'd have to pay to pee, I'd have held it.
[Photo via @madracket]