Something occurred which rarely does. I ventured out in the purpose of being social. Or presuming to be social. Or pretending to be social. This occurs sometimes in the comfort of known persons. It rarely occurs around strange unknown persons. Some points emerge.
Meeting strange people is easier if it is known some basic character traits ahead of time. In this case, all of us were atheists.
Meeting strange people is easier if it conducted with the auspices of minor intoxicants.
Meeting strange people is easier if there are familiar people around. Or somewhat familiar people.
Atheists like to gripe a lot about religion. I get the feeling this is because most atheists were raised under religious conditions. I only really gripe about it when religion intercedes on the basic liberties of people who don't share a particular faith. Some of that shit is really dumb I have to admit and some of it is really harmful to impress upon people. But. These are human beings we're dealing with. Stupid shit that other people believe is part of the deal. Religion is not the whole scope of those beliefs, it just happens to collect some of them together in a neat little package that is easy to either accept or mock.
I think I would prefer atheists meeting to do... things. Conversation is a part of conducting some activities. There is only so much value in meeting to complain about things we all agree upon. This is reassuring, maybe therapeutic, or provides some psychological value. In probably the same way that religious people seem to enjoy gathering at ceremonies and rituals of their faith. Perhaps it needs to be done at times and has its own set of enjoyment in having new conversations with strange people or old conversations with strange people. But. Doing things a) potentially helps other human beings in need of help and b) demonstrates that "we" are not eating live babies or some such, or whatever it is that "you" people seem to think atheists do when they get together.
Mixed gender or sexually oriented groups of atheists have unusual conversations. Or maybe mixed groups of all humans do, but this seems a persistent observation among secular people that they are usually more comfortable with some conversations than is the norm.