Since all of them (minus Employer Health Insurance) involves the state, not they cannot be duplicated without state involvement.
Taxes - government recognition
Veterans Burial - government recognition
Legal Next of Kin be default - government recognition
Social Security - government
Military Survivor Benefit - government
Military Change of Station Orders - government
Immigration - government
Protecting Your Visitation & Decision-Making Rights | Resources | Human Rights Campaign
Okay now that is settled. What laws in regards to marriage are authoritarian ?
When the patient has been in an accident hospitals only allow next-of-kin to visit in the ICU and to make medical decisions. Civil Marriage establishes the spouse as next-of-kin and provides that without prior medical documentation, that the spouse is the one that makes life and death decisions.
Can't answer, as again you call them "problems" - when they are not.
I'm simply pointing out that those things don't exist without government recognition of the establishment of a next-of-kin relationship, what we in reality call Civil Marriage recognition of a "Spouse".