My personal opinion is that religion shouldn't come into recovery at all. Recovery is an amazing thing, and it makes me so sad when people undermine their own strength and ability by saying that God helped them through it.
But, that's my personal opinion.
If you're looking for other reasons why people dislike it, check out these threads:
TWLOHA
TWLOHA
#to.write.love.on.her.arms
To Write Love On Her Arms is going to be at The Bamboozle!
TWLOHA
... I could go on, but hopefully these'll give you an idea.