Maybe, a little OT, but here it goes:
It's the same struggle here in Portugal to try to get the new generations in.
One of the problems I think is that in some cases orgs, oriented for the youth, are managed by non-youth naturists, so to say. Even if someone has a young spirit (but is 55yo) he will act and decide differently from a real young one and that will have a negative reflex in terms of linking ability to bring youth generations. In the end, youths prefer to connect with the same age range of people than with older ones. That's a fact and people with responsabilities in the orgs should think more seriously about it.
Anyway, clothing-optional resorts are a good way to introduce people that maybe want to give it a try if they felt comfortable with and they, in the end, will definitely try and enjoy it. That, nobody of us (at least) doubts :)