Ok, I have figured out why conservatives don't want same sex couples adopting, or even single LGBT persons adopting. It isn't religion, or morals, or any of those tired old excuses. Conservatives just know that LGBT folks are generally liberal and if they raise children in a liberal household they will most likely become liberal too. So they make sure as few liberals as possible are able to adopt.
Its a conservative conspiracy I tell you!
They don't want them turning our kids into liberals. That does make a lot of sense. More specifically they don't want the kids to turn into immoral, smoking, drinking, bisexual, donkey show viewing heathens.