Marc, this is a tough one. When I started in the MV hobby around 15 years ago, I was one of the youngest guys into it. I was around 25 at the time.
There were not too many guys my age for sure and it seemed to me most were my fathers age or older.
Over the past few years we have seen a few more younger folks come in.
I think a lot of it comes down to money more than anything. I think it is relative to one's status in life and how much spare change you have. Most younger guys don't have it. I was fortunate enough at the time to have had a really great job, live at home and had few bills and few responsibilities.
It is like the muscle car revolution... back in the day every young guy had one and the price point wasn't bad. Over the years these same baby boomers are wanting to get back in touch with their youth and supply and demand has caused a great increase in prices of 1960's and 70's muscle cars...
As far as sales from collector to collector, at least the goodies are staying put and are appreciated by the right people. Museums are the last place to put them and young guys who want to modify them are not the way to go neither...