Lame_Wolf - 12:12 pm on Mar 12, 2013 (gmt 0)
Because it's off topic crap for most sites and a topic many might find offensive.
No less, or more, crap/offensive than main stream religions. And no more, or less, off topic than the adverts that follow people around, or the general off topic adverts that appear all over the place.
Block them if you wish, but they pay well. I once ran an esoteric site for someone and it paid £1+ per click.(and pays more than the Religion category)
I'd rather have them on my site than mobile-phone, fat-belly, auction houses, price comparison adverts.