From Zelda Wiki, the Zelda encyclopedia
To rent-a-mod is to act like one of a site's staff, or moderators, and actively try to discipline others as though they have a moderator's authority. Many sites view this as an insult. Some sites, like Zelda Wiki, have a more positive view of this act and actually encourage it, as the site staff cannot be everywhere all the time, which is generally the case for wikis.
However, forums often discourage, or forbid, rent-a-modding, as it generally causes the moderators more problems than it helps. For example, if a new member posts a topic in the wrong section, and four members jump into the thread to tell them off for it, a moderator entering the thread now has to deal with four off-topic posts in addition to moving the misplaced thread.
The suggested method to dealing with a post found to be against the rules is to contact a moderator via a personal message or use the report function located next to each post. Most staff are far more lenient on rent-a-mod posts when the post also addresses the actual topic of the thread rather than just complaining about another post. Critics of this policy claim that this is being selfish and self-centered.