i think its either 'compensation for something' or showing their friends how powerful their laser is, by pointing it at an aircraft.
Or they could think its just a prank, and not actually a serious safety hazard...
I mean seriously, no matter what kinda power laser they can show their friends, i'll always ALWAYS have a more powerful laser (I do light shows)
I think the prime reason is to play a prank/see how powerful their laser is.
my kind of laser example:
