“Societies have celebrated marriages for thousands of years..”
since long before governments got involved and required they be registered with them
At the founding of America, marriage had to be legal, or it was not recognized by law.
That has been the fact for thousands of years, whether it was a law voted on by free people or their representatives, or tribal law, or the law of a single ruling religious authority, for instance an Islamic theological power, or the Catholic church for a while for some Europeans, after Rome fell, whatever authority it was, it was the law, what you and your mate called marriage outside of the law, wasn’t legal to the society.
Americans always lived under the marriage laws of our own, but if you don’t care if your marriage complies with law, then don’t comply, you could do that in 1790 and you can do it today.