Getting the state out of the marriage business

When my parents got married--way back, and in India--there was no concept of marriage license, or registering the relationship with the state.  It was a family and a community affair.  The publicly celebrated event, conducted literally in the middle of the street, as was the practice in villages and small towns across India, made sure that everybody in the community knew who was getting married and to whom.  That was it.  It did not involve the state.

The state really has no business whatsoever in being an authority to bless a marriage.  How did the state ever end up in such a powerful position?  I suppose it is all because of taxes.  For whatever reason, when it comes to income taxes, married people are treated differently from unmarried ones.  Children also become "tax write-offs" so to speak.  Which means that the tax collector has to certify these relationships and, presto, the state becomes the marriage license broker.  From taxes, it slowly spread to all other benefits that married people get from the state or employers.

But, the role of the state is to merely ensure that contracts are implemented and not violated.