Very true. When my older brother was in Japan a few years ago, he said that pretty much every store he went to sold models, and not just a little Walmart-like selection. Look at the kit manufacturers and detail of most Japanese produced kits and ask again why the hobby is so large over there.
And on a second note, younger builders (my age) can be easily introduced if they see a friend of theirs building a model. I managed to get 2 or 3 people interested, have friends that do build, and have talked to others that have built models in the past. Then again, most of those friends mentioned have interest in vehicles and mechanics.