A big problem with Argentinan football is that the hooligan groups or 'Barra Brava' are huge business and often have ties with the higher ups at the club. Its not in the clubs interest to police the situation as everybody is taking a piece of the pie.
These hooligan groups control everything in and around the ground. I went to Boca vs River recently. When my gfs uncle parked the car, he had to pay a member of the Barra Brava to 'look after' his car. Basically if you dont pay, another member of the group is likely to smash your car up and steal anything you dare to leave inside.
Football in Argentina is fascinating but farcical, the culture that is. The actual standard of the league is pretty poor with any talent moving to Europe very early(its said that the Barra Brava even get a cut of transfers!!!)
In regards to the article, banning away fans might reduce violence but I doubt it will prevent it. It's not un-common for rival factions of a club's Barra to fight with each other.
If you're interested in this kind of stuff this is an interesting article
http://m.guardian.co.uk/football/2011/aug/21/argentina-football-gangs-barra-bravas from a couple of years ago.
Also youtube Danny Dyers International holligans. He did one in Argentina. A lot of it seems staged but if you can get past Danny Dyer showing how much of a rudeboy he is, its pretty interesting.
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