Tony,
I hate to say this, but I think we are just showing our aging. It's a natural occurance that as the years advance the cars/trucks we grew up with are becoming antiques. The '67 to '72 body style is also growing at the shows, granted not as fast as the '60 to '66, but in 10 years I'd bet they will be.
When I purchased my '53 back in the 90's I wouldn't have looked twice at one from the 60's - now I own two.
