You say that in such a rational matter of fact way, but the reality is football plays on our tribal instincts. Evolutionary instincts that aren't going away and do date back to our primitive past.
In a civilised society those callings must be supressed but they still remain just beneath the surface.
Add alcohol into the mix and I can see why it kicks off among young men, who are programmed to be tribal and enjoy a good tear up.
I dabbled on the fringes in my youth, was never a hooligan but on a couple of occassions got swept up in it when it kicked off outside the ground.
When I was growing up and on the night club scene it kicked off most weekends, but I grew up in an army town which was renowned for it. You either fled or you threw a few.
I think its different today with the half and half scarf crowd and I don't think its quite as tribal as it used to be.
Is it a good thing? probably. Means women and kids feel safer going to the football.
You are engaged in such tribal thinking on some level by even supporting the club, the degree to which you are invested depends on your own emotional ties.
You might look down at the violence aspect but you are still drawing on your base animal instincts, the tribalism and feeling of belonging to a tribe that very much comes from primates/Cave people.
As I say we have to supress it in the interest of society, but lets not pretend it isn't there. in all of us.
Incredibly my entire life I've drank alcohol and been to football games and managed to resist the urge to punch anybody, so I'm sure all these very tribal other young men can manage it, the way that 99% of society does.
Otherwise they can end up in prison, where they belong if they can't behave in a civil manner. I imagine when they get there they'll discover they're not as big or hard as they think. There's no justification for it whatsoever. We may have 'primitive' instincts but we're hightly intelligent (well, some of us are) and don't grow up in a jungle.
Again, the vast majority manage to avoid going on a tear up at a game. So the idea that its just within us and we should just accept/tolerate it is nonsense. We've come a long way on this issue and should continue to clamp down on it wherever possible.