Sadly, this is a human trait overall. It's deep in the lizard brain section from early in our evolution.

If someone is part of a group and then does something seen as against the interest of the group (or groupthink, really) then any tiny little thing can become a trait leveraged against them. Either the person on the outs basically accepts demotion on the social ladder and hopes for re-acceptance from the group as subservient to everyone, or they're just out for good. It's one of our worst traits from a rational perspective, it's violent and irrational monkey-brain shit, and likely made for small homogeneous, tight-knit groups that could count on each other to survive harsh environmental conditions.