Society already has a certain level of enforced moral behavior. Making murder or torture illegal is based in morality. Problems arise if we get to less universal. That some things are illegal in one society, but legal in another is also often a consequence of a certain morality in that society. How much morality is "universally accepted" in a society to make violating it something which should also be against the law is a contentious issue. Personally, I think it's good to err on the side of "let people decide for themselves" and only make it into laws in exceptional cases.