If a drunk can't go to a meeting, where the hell can he go? As long as the drunk isn't disruptive I've never seen it as a problem. I think I'd have a problem with any AA who asked someone to leave a meeting just because he was drunk or smelled of alcohol.
Having said that, I do understand people feeling uncomfortable with a drunk in the room. It's sometimes hard looking at me the way I used to be. But, there but for the Grace of God go I.