From what I’ve seen of this special journal issue on the anthropology of atheists, I’m not seeing the ground for building any single agenda for ethnographically studying atheist cultures.
One of the following titles is not from a real ethnography. Can you pick the fake study? Sociable robots, jazz music, and divination: Contingency as a cultural resource for negotiating problems of intentionality. You Have Dislodged a Boulder: Mothers and Prisoners in the Post Keynesian