I think its due to my country..here we don't have naked people walking around and i will always sustain the freedom of expression.
It is not illegal to walk into these neighborhoods without modest clothing on, but take into account that there is a different life style from yours in these neighborhoods, and for the sake of preserving their life style they wish to ask visitors to this area which are about 100% unanimous on their designs to keep the area modest, to dress in a way suitable. You have every right to determine how people dress on your property, etc, and it is your way of thinking that determines what is appropriate, now when on samenesses property, it is only natural that you should respect their wishes.
Would you not be angered if a man and women ran around your backyard, or drive way completely naked? What if they were just on the side walk naked, and your kids were watching them? Would you report it, or would you be angered? To the people in this neighborhood, a mini-skirt, and revealing clothes is compared to nudity. Therefore, a level of respect should be given to the people who reside in the area, if you wish to do business with them in anyway. It is not against law again I repeat to walk through there in immodest attire, but I doubt people will do business with you, or hide there disgust, same way as if a nude man ran around a "
secular mall".
And we have mixed neighborhoods....none from us never felt the urge to make distinguished neighborhoods like in states.
It is not like non-Jews are not welcome in these neighborhoods, it is just that traditional Jewish households average around
8-10 children and are married by their 20's. Therefore, real estate is very hard to find, and non-Jews find it uncomfortable to live in these traditional Jewish enclaves. The Jewish areas since the populations of these people double ever 15 years or so, (1985 there were 100,000 in a certain area in the USA I will not name, now there are 200,000) the area naturally becomes entirely Jewish.