I'm not saying what these mods did is or is not scummy. Rather, I'm looking at Reddit and the way they perceive the communities that live on their platform.
Trying to monetize a subreddit isn't really the purpose of the site, and if you want to do that there are other tools available.
They host the website and have the user base.
And moderators create subreddits which they control.
The web comic xkcd's subreddit had a holocaust denier as the top mod. In 2014.
Reddit didn't step in even though the comic's creator didn't like it. And other mods and the community asked for it.
They were only removed once they were inactive for two months.
Summary I found: https://www.dailydot.com/unclick/reddit-xkcd-moderator-socce...
Reddit never had any problems hosting white supremacists, pedophiles, psychopaths and criminals as long as news networks or authorities didn't get involved.
User count is more important than morality, ethics, humanity or moderation. Reddit also tends to casually lie about this. The creepy smiling Smoo says it all.