I'm 34, been collecting old gas for about 3 and a half years now. I started collecting coins/stamps at 10 years old, then as I got older and started working, the ability to collect rarer and better things started me collecting 1930's movie memorabilia, autographs, and 1930's Disneyana, things I could not afford when I was really young. I guess that's how it works, the more money you make, the more you spend on your hobbies!
Growing up my Dad had old gas items around the shop, the best items the two Sinclair Aircraft DS porcelain signs that covered holes in the barn floor when Dad bought our farm in '73. I think growing up with the stuff you have an appreciation for it others might not. I would guess even though some people on here say their kids don't appreciate the stuff now, at least the seed is there for when they get a bit older they could grow into a future collector. Maybe not as young as some of us, but I'm sure when Dad meets his maker, they will probably keep a few Petrol items around to remember Dad. Hopefully that might lead to more collectors in the future.
I guess either way, whether or not the stuff is worth a lot in the future, I enjoy my collection very much and I guess that's the point of having it. I really enjoy walking into my apartment and being greeted by hundreds of Flying Red Horses. My visitors love it too!
Have a good one all,
Darin