Conversely, the mods can also be mercurial and act like little tyrants over the subreddit. /r/StarTrek in particular is known for stifling criticism around 'new trek' and spinoff subreddits like /r/DaystromInstitute were created by people tired of the mods' actions.
It also raises an interesting question as to why the mods have so much power in the first place and if any community recourse should exist when subscribers do not like the mods' actions. For one thing it does seem weird that the mods of r/StarTrek are allowed to unilaterally close the subreddit.