Gender rules

I wonder why gender specific dress codes are allowed. Has this ever been legally challenged? Why is it women can have pierced ears, but men can not? What about long hair? Don't give me the "it's more socially acceptable" argument...doesn't fly with me. Women fought...are still fighting, for the right to be treated equally in the workplace. We can wear pants and do dirty jobs with the best of them. Isn't there anybody out there arguing for men to be able to have the same freedom of expression that women enjoy? OK, I know there is somebody asking...what if men want to wear skirts? You can cut the sarcasm. I have no objection to a man wearing a skirt. You may think hair length and earrings are trivial matters, they aren't to everyone. Why do we tolerate gender specific rules? Aren't we supposed to finally be better than that?