"anyone joining those teams who doesn't behave like that either won't get a game or will incur the wrath of the herd."

That's what happened in the Japanese Army in WWII and caused so many horrible atrocities to be committed by their troops in China and elsewhere. A few utterly brutal officers and some sadistic individual soldiers used their position to manipulate everyone else in the unit, the end result being that a large number of essentially decent, normal, and patriotic young men were turned into complicit war criminals. It only takes a few rotten apples to spoil the entire barrel. It happened in most other armies too, probably in all of them...but it was almost certainly the worst in the Japanese forces. Anyone who had kinder or more decent intentions toward prisoners or civilians wouldn't dare show it in front of the others...unless he was the top commanding officer...and even they were afraid to show it, lest they be thought "weak". It starts out that way and it just keeps getting worse, because the macho types who cause it are always trying to raise the ante one step farther to prove themselves to each other.

It's a sick, sick business, whether it happens in war or in the world of team sports.