The government has no place in marriage.
If the gubmint is handing out cash to single moms and fatherless kids, the gubmint has a big interest in marriage. The whole point of marriage is to unite moms and dads with their offspring so that kids have the best shot at being successful citizens with the support and tutelage of the people who created them. Now if you want to ditch government support to unwed moms and the kids, then I might agree with you.