This is my point: the "atheists", the "homosexuals" (or any other group that regularly slams Christians) will not start a community of their own. Why do you think that is? There are places where towns are for sale. There are large tracts of land where a group could start their own community (gated or otherwise). Why don't they? Why do they choose to live in family oriented communities (usually largely Christian)? Why do they then feel insulted when a neighbor invites them to "fellowship"? They chose to live in a place where the beliefs of the majority of the people are Christian?
How many of those same people would choose to live in a "muslim community" and then mock and ridicule the muslim faith?
Your point is why don't atheists or homosexuals or whatever other groups you don't like here start communities of their own? Why should they? Just because someone shares a lack of belief, or sexual orientation, doesn't mean you want to live around them. This is obviously true of Christians as well. Why don't they buy a town or start a community? Perhaps most are either happy enough where they are, or not part of any large groups that could do such a thing, etc. You make it out as though atheists generally segregate themselves from the rest of the population, or homosexuals do, or the other groups you consider Christian bashers. I think that's a misrepresentation of reality. While certainly atheist and homosexual groups do exist, I question whether the majority of people who fit those categories are part of said groups, and I question whether they consider isolating themselves from people outside those groups a good thing.
As far as people from these groups you dislike living in largely Christian areas, aren't MOST parts of the country largely Christian? If somewhere from 70-80% of Americans self-identify as Christian (I've seen multiple polls that put the number somewhere in that area), wouldn't it, in fact, be hard to find places that are not made up of mostly Christians? So, the idea that these Christian bashers are specifically going to Christian neighborhoods seems ridiculous.
There are probably few people who would argue that there are admirable traits to Christianity. It may even be that Christians are better able to get along in a society than any others. It is a very difficult hypothesis to prove, if it isn't impossible to do so. There are simply too many variables involved in what makes a good nation, even a good community.