Football hooliganism has been a part of English Football for many years, we can look back to 1970/80s when it was big news.
Just because it doesn't hit the headlines as often as it did back then, doesn't mean it ever went away because it didn't.
The police stings of the 1980s, did manage to help jail some of the ring leaders amongst the firms of the day and some hefty sentences were given out.
The advent of CCTV made it a little harder for the hooligan not to be spotted on a busy match day in areas around the city and grounds.
So pre-arranged location were and still are chosen between rival firms so they can have a ding-dong.
These firms are not made up working class uneducated people they are made up of varying degrees of Intelligence and class.
As much as people may believe that this minority of people are not football fans, they are so wrong, they live and breath football they love their club and the game but also have a desire to fight for their club in streets.
Behind closed doors matches, wouldn't resolve the problem as these people don't need a match to arrange a scuffle.
I don't know the answer, but don't think it ever went away.