Freedom of religion is part and parcel to our culture and constitution of the US however that should mean that any church that does not practice same sex marriage should not be forced to perform the marriage and register that union under thier church documents. Civil unions should have equal rights legally as per any business relationship. If they seek a religous confirmation of that then they need to join or have sanction by a church that approves such unions I am sure given the history of Priest Craft or rent a conection to God it should not be hard to find?