This is an incredibly stupid argument. And, he's clearly talking out of both sides of his mouth.
Government provides the definition for marriage because you need society at large and the legal strucure to recognize marital relationships. As such, it shouldn't discriminate.
What the hell does this mean? How would you protect the equal rights of same-sex couples, but not let them get married?
Maybe when the officiant asks if anyone objects to the union, the state can provide conscientious objectors to stand up and object on behalf of the state.