Have you ever heard of European football? People are being killed routinely during opposing team fan "meetups". https://idrottsforum.org/alsio130118/ Raging kiddie gamers are a joke by comparison.
2001 Opatów, 2003 Walichnowy, 2007 Kielce(knifed), 2007 Łódź(coma), 2011 Poddębice, 2011 Kraków, 2018 Prokocim(arm cut off with machete, body massacred with baseball bats, axes and hammers). Thos eI could find with a quick google.
Example clip from one https://www.youtube.com/watch?v=jKXOsC3ms7k train was emergency stopped in the middle of nowhere, other team was already waiting after being transported by shuttle buses. You can search "Ustawka" on YT for more.