Gary,
Because I love the game, I hope you were being a bit overly pessimistic and I hope I am not being unrealistically optimistic. Most of the people on this site get a real kick out of golf courses, not just the game itself. But I think the aesthetic pleasures of the game are lost on most young people. When our boys were young, they played on summer hockey teams and when we'd travel to tournaments I'd always bring my sticks and try to work in some golf along the way. Entering one park, we crested a hill and before us was a beautiful scene of forest and hill and sky and I commented upon it to my son, to which he replied in a matter of fact, almost reverse paternal tone, "Dad, I'm 13 years old, I really don't give a crap about trees and clouds and hills".
The 12-25 age group is certainly not a demographic that can be ignored. It is those young people who are passionate about the game through their twenties that draw others into the game later on. That's what happened to me. A friend I used to play squash with who was a scratch or plus golfer and had competed at the top amateur levels in Canada as a kid, invited me out to play one summer and I was almost instantly hooked, partly by the game, but also by the grounds for the game. If it had not been for a peer of mine like him, I may never have taken up the game.
I think there may also be an element at play for those less than athletic people, like those at your reunion, that turns them into hard core golfers. When they play, they get addicted to the sense of achievement from getting better, a feeling they may never have previously experienced from athletic pursuits. This sense of achievement may be missing for more athletic types that played golf during their youth, who become frustrated trying to recapture what they were once capable of.