When I went to meetings, though I'm an addict, I went to AA..including closed meetings. I never talked about my drug use, I just used the words "not picking up" and that seemed to work.
There were a few people who didn't like addicts being in the meetings, but it was very few. I talked to people AFTER the meeting and explained what my REAL problem was and several took me under their wing and when someone new would come in with addiction problems, they sent them to me. I'd say half my home group had, at least, problems with drug addiction, if not that and alcoholism.
I learned, early, to look for the similarities, and there were a lot. A craving is a craving...I just never mentioned MY craving was for opiates (this was before I discovered crack....sigh).
Yes, there are other meetings and many are much more open to addicts, because more and more people are cross addicted to dope and alcohol. I didn't really every feel like I fit in with NA.
I recommend your friend talk to someone after the meeting, explain that though he's an addict, he is more comfortable in AA and is serious about his recovery. They can probably tell him how to word things, not talk about dope (all the stuff I said above), and he will be fine. If not, seek another meeting.
I did find, too, that in a number of meetings (I went to several) there were a few people I just didn't click with. Heck, we're all recovering A's and some still have issues. I found people that had what I wanted..recovery, open minds, and serenity. Those are the ones I befriended, and always listened to.
One other thing...I always introduced myself as an alcoholic and addict, because there WERE times in my life that got out of control with the alcohol and couldn't stop at just 1, so I felt that qualified me. It had been years, but hey...it was the truth and it worked.
Hugs and prayers,
Amy