You miss two very important points.

1. The reason our constitution is set up in the way it is is to keep your individual "private beliefs" out of government since we do all have our own beliefs, and if there were no laws governing them, then we would not be a country governed by the rule of law but we'd be an anarchy....each man for himself.

2. As to the discrimination thing...you are perfectly right. You can discriminate all you like PRIVATELY, but the government can't, which is the point of the CA Supreme Court ruling.