There used to be AA/NA meetings for atheists but they were a pain in the ass to get to usually. Churches love to host and sponsor those meetings to take advantage of desperate, addictive people and get them hooked on god to increase their weekly take. The atheist meetings are usually held way less often and in locations that are off the beaten path so they are hard to attend for most people, at least that was my experience when looking into them way back in the day. I suppose YMMV depending on your location.