Keeping the old stuff around is actually really, really expensive. For the price of restoring my RC30 I could have bought a really nice track bike, or a new dirt bike. And the older the stuff is the more you need to know about engineering and machining. My bike was a great education in welding, fabricating and CNC machining. It was a lot of -fun but now I don't dare ride it due to a complete lack of spares.
I'm looking forward to completing the coach training. I'm really excited about riding with students all over the country. And you're right, the smiles make it all worthwhile.