Well, I will never understand why the very people who rail against someone hurting another person want to hurt that person - and then to wish that someone else would do it for you is really beyond me.
I understand what you're saying but this is just a question of people blowing off steam.
I'm sure LE says the same thing about some criminals they encounter.
The IMPORTANT thing here is that there's a big difference between 'wishing' & DOING.
As long as people aren't taking actions OR looking the other way so somebody else can take action.... it's a 'healthy' way for people to vent.