You wouldn’t want the government making decisions based on what a religion (say, Islam) considers holy or unholy, right? Probably best that the state stay out of the business of holiness altogether, don’t you think?
No I do not want unholy unions based on what God says.
If you want to get in a discussion over what the government wants or does not want I will.
Marriage is a Holy union -a man and a woman - period. Anything other than that is unholy, regardless of what the government says or does not say.