they're not looking for something straight people don't have, they're looking for what they do have. and the analogy was that in the case of adultery the laws of god do not dictate the laws of man in a nation that bases itself on separation of church and state. no one is taking away YOUR right to condemn gay people/marriage, they're just saying your disapproval should have nothing to do with the law. just like it doesn't with adultery, premarital sex, etc.