I agree, and this brings up the subject of Nazi wikipedians, or satanists, or communists and anarchists for that matter. People are allowed to be themselves, so long as it doesn't break a rule. Being these things isn't against our rules.
Well put, Jack. And besides, there's no way we can stop paedophiles, nazis etc. from editing. We could forbid them to state their bias on their user page but that would be counterproductive.
Many people state their bias on their user page, be it religious, political or more personal. This is sometimes useful for other editors - it can help to know where someone is coming from.
Knowing someone is a paedophile, for example, alerts others to places where she may be letting her personal desires cloud her judgment.
Other people prefer to be as anonymous as possible and give no personal information on their user page to make sure that they are judged entirely on the merits of their edits. That's fine too.
Regards, Haukur