They're not unique in this behavior. Basically every political subreddit that exists, and even some that arn't innately political but get taken over, do the same thing.

I remember there were a bunch of posts in /r/zerowaste about someone explicitly advocating to be made a mod so that they can moderate the subreddit as an anti-capitalist. I really had to credit that person for the bravado of saying: "I'll ban people I disagree with, voooote for meeeeee".

In fact, the ONLY political subreddit I'm aware of that does not engage in this behavior is r/Libertarian. Credit to them for putting their money where their mouth is.