Moderators that are often anonymous/unknown.

(This isn't an argument against your point, just a bit of additional context that increasingly is odd to me as Reddit gains more and more social weight)

Very true. Fortunately I don't think most moderators want to see their community destroyed. That's exactly what would happen if they started taking money. As a group, people will catch on fast and either force the moderator to step down or just leave for a new subreddit.