Uncanny timing of this thread... finally just got this published in SAM (look for it in January print edition also): http://www.saminfo.com/article/speakout-where-are-all-moguls
That all said, the justification for moguls IMHO can't just be because people are nostalgic about skiing moguls from the heyday of their youth. Moguls are fun, offering variety, moguls are a challenge and keep you mentally engaged.
I don't think it helps either that the most exposure people have to moguls is zipper lines at the Olympics. I was once interested in a summer Mogul camp at Timberline, but the description was more about competition zipper lines along with aerials, neither of which interests me.
I'm 51, I want to ski bumps with confidence, control and grace, while saving my knees so I can ski moguls for another 51 years.