Problem 1: I think one of the worst problems with this is that "obsessed fans" think every single bit of trivia needs to be covered in its own article. Wikipedia works best of its information is structured and thus put in larger articles with context.
Problem 2: People try to slip in self-promotion and advertising for bands, forums, books and scores of other things which either cannot be expanded into a full article or are simply not encyclopedic material.
Problem 3: People get problem 1 and 2 mixed up. Not every trivial detail needs deletion, a lot can be merged or put in a sister project.
Wikipedia is not an indiscriminate collection of facts, so not every single bit of information gets in. We are first and formost an encyclopedia, not a data dump.
--Mgm