It is entirely reasonable for people not to be free to wear what they want without restrictions placed on them. There are dress codes in many, many places and not just for women. No shirt, no service? That's about men dressing appropriately.
And I'm entirely reasonable in not wanting to see arses in my workplace. For my benefit. I don't want to see penises, or men with no shirts either, but that hasn't actually come up as an issue.