As an occasional flier like 5 times a year, this is what tilts me.
1) When the pilot turns on the fasten seat belt sign, people ignore it and get up to use the bathroom or get shit out from the overhead endangering everyone else
2) People that put on their seatbelt before the window seat is occupied, therefore wasting time unbuckling while others are waiting behind the guy trying to get to his window seat
3) I despise people brining smelly food on an airplane. If you are that hungry eat before you get on the plane. WTF? You can't wait a couple hours? You are that fucking hungry?
4) People chattering and laughing when there is turbulence. It needs to be completely quiet during these times
5) Fuckers that sleep and snore. STFU and wake up and get a cocktail, you are annoying everyone