yes this is part of it, a general low tolerance to scumbags and you view them all the same. if the last 5 guys you chucked out kicked off, your going to assume so will the 6th. Its also easy to get carried away a bit if no one is there to stop you, end of the day its a bit of an adrenaline rush so you all become adrenaline junkies wanting something to kick off in the club so you get some action plus the whole mob mentally can kick in a bit. its great banter choking people out with your mates helping. as for the police, half of them are thrill seekers as well, no one joins the police to write speeding tickets (well maybe in nsw).
In scotland there is a big knife culture, on the doors your always warey of it (despite only having 2 blades pulled on me in 10 years). someone telling you they are going to stab you is a pretty common threat and you hear it alot. How ever if someone says they are going to stab me or my colleagues, and you see their hands go near their pockets or behind their back..they are going to taste pavement. The law also support you in this, if you believe someone to have a deadly weapon on them you technically use up to lethal force to defend yourself (although would be a nervous trial!), you dont actually need to see the weapon. This is the reason cops are pretty trigger happy in the states. Why give some gangbager the chance to pull on you? If i was in those situations I would unload on the kunt first chance i get too. People can cry brutality but 90% of the people who get rinsed by the cops had it coming, sure some innocent people get it too but its rare. Its an even playing field in the states, everyone is packing so you have to be hyper vigilant as you have no advantage over them. Here cops have guns and we dont, so its much safer for them to peform an arrest. In the UK they only have baton/spray and taser, which again is a big advantage. Seen a few people get hit with a baton or sprayed with CS gas, all had it coming.