I heard on TV the most interesting comment today in a discussion of race. One of the commentators said that Sundays were the most homogeneous time of the week in America. By that, I think was meant that white people go to white people churches and blacks African-American churches and Hispanics mostly Catholic (but, increasingly, megachurches) and the twain seldom meets. That is, there is little admixture of racial types. So I think it is a tribal thing. "Community" is a possible word for it, all right. It is a social setting and that aspect of it will be the most difficult one to die out. I suspect many church-goers go primarily to be with people they know, to feel a sense of belonging to the community.
I was brought up Episcopalian and went to a local church called "the Church of the Good Shepherd." An acquaintance corrected me when I mentioned that, saying, rather, it is the Church of the Good Cadillacs. I knew what he was talking about and got a good laugh. It is where most of our doctors and lawyers go. When I informed my mother at long last that I was an atheist, I was amazed when she told me of an incident on the front steps of the church one Sunday -- amazed because it confirmed everything I had been saying about her church. She said that after the service, she was socializing and got into a conversation with a local federal district judge. In the middle of the conversation, a prominent attorney came up, struck up a conversation with the judge, and pulled him away to discuss something apparently important. Mind you, this judge terminated memberships in several local private clubs, e.g. the Country Club, the Yacht Club, &c., because of the "ties" they imply. But here he was being ex parte'd by an attorney -- on the front steps of the church.
My mother chided me, "Perhaps you would be more successful if you went there every Sunday, too." I think anyone reading this knows what I said in response to that.