Yes. They have the right to equal treatment. They had their day in Court and lost. Too bad, so sad.Opponents of gay rights often warn that legalizing same-sex marriage would inexorably lead to legalizing polygamy. Maybe it would, and maybe it should.
Denying gay couples the right to marry violates state constitutional guarantees of equality, as the California and Massachusetts high courts have rightly ruled.(The Supreme Court of California also held that the right to marry is fundamental.)
Surely polyamorists have the same rights to equal treatment under law.
We don't allow children to marry. Are they being deprived of equal treatment? Yes. And the Court gave legitimate State reasons for doing so.