Presumably she thought the passenger was just being facetious and was going to take the jumper back off as soon as she wasn't looking. (I saw something like th

Presumably she thought the passenger was just being facetious and was going to take the jumper back off as soon as she wasn't looking. (I saw something like this 3 times on a Delta flight in which there were empty seats and the passengers were asked to not move from their assigned seats until after takeoff due to weight/balance concerns. They asked a passenger to move back, and as soon as the flight attendant turned his head the passenger moved back into the empty seat...this happened 3 times before the flight left the gate. I would have gotten pretty pissed as the flight attendant and was actually pretty impressed by how calmly he handled it.