I think a lot of it is just ignorance.
My uncle is a pastor in West Virginia. I heard him say last time I saw him that they'd have to throw him in jail before he marries a gay couple. He literally thinks if they legalize it he'll be flooded with gays getting married and that he'll be in legal trouble if he refuses to do it.
IMO, the legislature is just punting because its not something they want to deal with one way or the other.