Appalling behaviour on planes and airports

[LionKing]

I hope this doesn't cause any controversy here.
What is the most appalling behaviour you have seens on planes and airports in recent years, particularly post-COVID?
I still recall Alan Joyce saying some passengers are not 'game-fit' , and that reminded me a video of a China woman where she talked loudly on a phone before takeoff, another passengers filmed her and that started a quarrel and that video became viral just last few weeks.
Another video I saw another passenger refused to swap seats with another passenger who had a paid seat selection, and the man simply 'accidentally' splash' liquid at the other passenger mid-flight.
What can we do as frequent flyers help to diffuse these appalling passenger behaviour?

 

[Pushka]

I think I've been lucky given I've travelled back from Bali on Jetstar at midnight. But the thing that sticks in my mind was in J and a guy was walking up and down the aisle brushing his teeth

What did I do? Cover up my eyes with a bandana (I have a Survivor one), turned over and went to sleep trying to scrub the image.

 

[AIRwin]

But the thing that sticks in my mind was in J and a guy was walking up and down the aisle brushing his teeth

He didn't want to hog the lavatory?

 

[Pushka]

He didn't want to hog the lavatory?

Maybe, but the walking past people was classic. But I think he was just a jerk.