People don't attend live art . . . except for the millions that do, around the country, every year.
People don't purchase subscriptions to theatre, dance, classical music, etc . . . except for the hundreds of thousands that do, around the country, every year.
The question is whether we are going to look upon those people as the exception or the rule.
Here's the reality, the only thing that we really do in mass anymore is watch certain shows (the NFL, American Idol) and blockbuster movies.
Everything else, including the arts (ESPECIALLY the arts) is a niche business. It serves a specific, smaller, audience and because of that it will never be the thing that everyone does.
The smart thing to do in this environment is learn how to maximize and leverage the audience you have. Complaining that the audience you have isn't big enough, or is too old, or whatever not only fails to solve the problem . . . it also makes those who do participate feel like they aren't appreciated.
Embracing the audience you have, however small it may be, is the first (and most vital) step to audience growth.