Ok, I can live with red dot sights and other low powered scopes but it just annoys me to see guys with high powered telescopic scopes on their AEGs.
Oh, and on the topic of snipers, another pet peeve:
Snipers who think they are the absolute shit. Airsoft snipers are useless. I hate these guys who snipe and think they're the heart of the team. Sorry to break it to you, but any AEG rifleman will be more useful than your average airsoft sniper any day.