Travel advice: Do not wear football/soccer T shirts while walking around in Argentina

I spend 6 months a year in Argentina, and i constantly see foreigners who know nothing about the local football culture, wearing football shirts they bought here a few days after arriving. That is a horrible idea. Here´s why:

• If by chance you come across buses/cars/trains full of rival teams supporters going to a match (especially during Sundays), the least it can happen is you getting the shirt taken away. They will NOT care that you are a tourist. Worst can be getting beat up.
• Most hoods have the majority of people supporting a certain team, and if you are walking around you might go from an area that loves the team whose shirt you are wearing, to an area where that team is hated. And i mean hated.
• At night, any street drunk guy that does not like that team will let you know.
• Teams from 2nd and 3rd division have very specific rivalries, which only locals are aware of. Tolerance for wearing the wrong shirt at the wrong place for those teams is slim.
• All of this is equally prevalent in most provinces, so its not just Buenos Aires.

You do NOT know the culture. You do not know the rivalries. Stay out of it.