I personally would never rat anyone out I met at a meeting (even if I was ok ratting myself out in the process). I find most people are in the rooms to get better. That being said, there is no guarantee. If my boss were to hear from someone I attended meetings, and if he were brash enough to approach me about it, I would simply tell him I was not comfortable having personal conversations in the work place.
worse case scenario, my work finds out, so what? I am getting healthier. I have no shame in my meetings, and you cant be fired for quitting drinking