When you're playing beer pong with your friends, and a friend not already in the game takes a shot for you.
"Leah was already trashed so she opted out of the BP game and I took a celebrity shot"
When you're bowling and you allow someone else to take your turn.
"Hey man, are you going to bowl your next set?"
"Naw, I'mma take a leak and let Bobby do a celebrity shot.