I think you’re mis-characterizing Christian morality. The Bible makes a clear distinction between merely obeying laws, and internalizing good behaviors. It even acknowledges that the former can be quite dangerous, i.e. from Romans 7:
“For while we were living in the flesh, our sinful passions, aroused by the law, were at work in our members to bear fruit for death. But now we are released from the law, having died to that which held us captive, so that we serve in the new way of the Spirit and not in the old way of the written code.”
There’s a tendency for some people to overlook the NT perspective on “the law”, a tendency that has resulted in such ironies as Victorian laws banning playgrounds on the Sabbath (well, Sunday.) And, of course, recent opposition to homosexuals.