Yeah, I more or less agree. David Sloan Wilson (an evolutionary biologist and professor of Biological Sciences and Anthropology at Binghamton University) argues something similar in his book
The Neighborhood Project: Using Evolution to Improve My City, One Block at a Time. though his focus is not religion as much as it is the evolutionary basis for social cohesion/networks. He also notes that similar benefits can be achieved through other similar organizations such as community organizations (school, work, extracurricular activities programs like sports, fraternal organizations, charitable organizations, etc [note: he does not argue for those specifically, but sees all of them as part of the larger whole of society, the examples were mine]). Personally, I don't see why other similar organizations (therapists instead of confession, joining together for charitable work instead of to sit in a room on a sunday morning, etc) couldn't or shouldn't replace those kinds of activities. I think in time they will, because they will be more beneficial to the individual and the whole.
Here is an interesting link to an interview he had where he spoke about 7 rules of prosociality that he came up with through observation of wasps and water striders and how they can be used in cities to create richer communities.
That is a very good question. Basically, I am asking when will we take organized religion as seriously as sacrificing goats to Zeus. You know, scratch that because I am not opposed to groups of people coming together and having abstract experiences that we don't quite understand that might be connecting us to some higher power. In fact, I think stuff like that can be a benefit for many, but I hate namby pamby bullshit religion that is just there to make everyone feel like they're "doing their part" without actually having to do anything worthwhile.