I don't know, but one of the most consistent patterns I've seen with chud posters, the kind that have just about zero post history in a place they get chuddy in until they post their chuddery, is tons and tons of nfl/nba or team specific fansubs.
My hypothesis is "social engineers" and freelance chuds build up karma points by nodding along in sports subs then go to /r/antiwork or /r/fuckcars to do one off bootlicking posts. It's weird but otherwise I don't understand the pattern.
Probably just chud magnets, or more simply American magnets. Hell yesterday with the Georgia v. Alabama there was no fucking traffic during the game. I went to a grocery store at 8:30 and I was the only one in there. Americans truely love their slop of combat and sports.
Football hooliganism and post-game riots are far from an American-specific incidence.
Western Europe likes to get rowdy about their soccer
is there the same culture of shaming people, especially males, for not keeping awares of sports things/ for not caring?
Yes
Isn't America almost famously pacifist compared to Europe and LatAm regarding sports riots? Most of what I remember regarding sports riots in America is just nerds being angry and lighting their own city on fire. Not even any violence, or clashes with the cops.