My RABF and I are both in our late twenties, and when he decided to stop drinking about a year ago, he got heavy into golfing, fishing, and running. As far as things we do together, we see a lot of movies, hike, watch tv series, cook, and eat out. He's usually okay with social things as long as drinking isn't the main event. Weddings are particularly difficult, it seems.
To weigh in on the moderation thing, I'm not a believer in that at all. RABF didn't drink for four years - when we started dating, he was in a period of thinking he could go back to drinking in moderation. It was nothing short of terrifying. He decided to stop drinking a year ago again and he's already had two relapses since so.. Yeah. Moderation. I think not.