Thing is, should we give the stamp of legitimacy to discrimination? Or should we give the stamp of legitimacy to freedom from discrimination?
Remember, men's-only voting had the stamp of legitimacy for almost half of America's history so far. Once women's suffrage was given the stamp of legitimacy, a lot of people (almost all men) didn't like it...but look how that particular stamp of legitimacy has changed our society. How many out there would even think of restricting a woman's right to vote?
So it goes with laws either allowing or disallowing discrimination. The longer the laws are on the books, the more the society adapts to and accepts those laws...and they become a part of the social fabric.