Well I can understand why a non religious person may not want to do that too. Laws should not make them do it. Gays should find people who are happy to marry them, Sexuality is a matter of choice! That includes choosing to be revolted by the choices of others.But nobody actually does anything against officials who, against the law, refuse to marry gay-couples.
Governments are not the powers they once were, it is a mistake to think that they can actually control what is happening.
Much of this mess is caused by the financial institutions having too much power, so much that they persuaded governments to try and bail them out of trouble. They should have been allowed to fail, evolution applies to finance just as much as it does to life. We protected failures so now we fail too.