I think users were pissed off because of the lack of transparency. No one knew what the admins were deleting. It was up to the community to find out which subreddits were banned and why. Further the admins never logically explained their decisions, for example, to ban fph over srs. From the outside it seemed like an arbitrary power trip. And for what? Reddit's moderation system is perfect: let users form their own communities and moderate them as they wish. Some of the communities will be terrible but that's the beauty of it; you don't have to go to them. This system is what let reddit grow to the size it is today. While hackernews takes a different approach (moderation at the admin level isn't unusual) that is only manageable for a site of a smaller size.