It is true that in Islam, we muslims have to protect some parts of our body from sight in public. Why? Islam is not trying to limit freedom but it understood the intricate nature of women's dignity. Women's body are beatiful albeit their size and features. Their bodies are pleasantaries of sight and are comparable to jewels and diamonds.
Covering of the aurah is a way for the public to judge women through their intelligence and personality, not the size of their breasts and the diameter of their waist. No matter how you so called Liberalist think that men is at fault when they stare at women who exposed their aurah, it is men's nature to be attracted to women and their beauty.
I myself come from a family who do not bother of the requirements of aurah covering and what can I do about it? Nothing. Unless the woman in the family is my daughter or my wife, lecturing any one of them about their choices of clothing is rude and downright degrading. They themselves have the responsibility of safeguarding their beauty and their decisions can only be judge by God.
And whether or not people who covers their aurah are better than those who don't is a misconseption. I, like you, do not have the right to judge people based on their appearances but we (especially men) can curb the sight of aurah by lowering our gaze and advise the women (nicely) to dress modestly.