Some of the things that annoy me about air travel:
1) Pax yammering loudly on their phones while standing in the gate area or on the aircraft during boarding or after landing. I understand quick calls to say "I've landed, I'll be out at the curb in a few minutes," but lengthy calls should wait for a more private moment, especially for loud talkers.
2) Airline agents who refuse to process last-minute upgrades at the gate out of sheer laziness, instead letting premium-class seats go out empty.
3) Lack of (or tardy) information from the cockpit in the event of rolling delays (those that are 5 minutes, then 10 minutes, then 20 minutes, and so on). Nothing is worse than sitting at the gate 10, 20, 30 minutes past departure time, with nothing happening and no information forthcoming!
4) TSA. 'nuff said. But in all seriousness, there are 2 things that upset me the most:
a) shoe removal
b) TDCs who take 60 seconds to examine each and every ID with the magic light