IMPORTANT NOTE: You do NOT have to register to read, post, listen or contribute. If you simply wish to remain fully anonymous, you can still contribute.
It's to reject Spam and Trolls Eric. All Forums get loads of Spam (that's commercial messages trying to gain publicity) and Trolls (people who just post silly things or nasty stuff or libels). We have several filters that chuck out most of those by recognising their IP numbers or fake URL's.
Then we have board keepers who read the remaining posts before putting them up and, if they are unsuitable or illegible or libellous, dumping them.
That way we (hopefully) keep the site interesting.