I don’t follow your point. Palimony is really no different a case than a disagreement/settlement between business partners, roommates, or siblings.
I don’t need a license to be a sibling do I?
Palimony is the result of 2 people who were shacking up and then split up and couldn’t manage to divide the property without “help” from the government. If you government out of the marriage business eventually the dissolution of these “private” marriages will drag the government right back into it. Did you notice how the other entries in your list all involve some level of legal documentation to START the relationship. That documentation is there to help the government dissolve the relationship, though palimony shows they can decide the documentation is implied. This is how government got involved in the marriage business in the first place, if you try to get it out you’re just rolling Sysphus’ rock back up the hill. In short order there will be enough deaths and divorces to get government right back in it.