I agree with another commenter that this not something that people consciously think about when they do it. I think the main thing you’re touching on is groupthink. This is the reason that groups of people behave differently than you’d expect individual people to.

Positions of leadership (and therefore power) as an institution are traits passed down to us from Feudalists who organized society in hierarchies. I would say groupthink allows these kinds of social structure to continue long past the point that people realize there a better ways because they assume other members of the group are okay with them.

That’s all not to mention the fact that some people are genuinely skilled leaders or that people in positions of leadership are going to have a bigger influence in what is accepted in the group.