1.) They adopt kids, preventing some abortions
2.) Times change. If we kept Catholicism to the way it was back in the day, you'd be on a stake right now burning.
1) If they adopt kids, their children are going to be miserable because everyone is going to tease them for having two fathers. I've known kids like that who would rather have been dead.
2) I'm a Christian(non-denominational).
3) Being homosexual is an abomination whether you like it or not. You can't change a religion for your personal prefrences.