As an experiment, if it is supposed to teach us about how much the masses appreciate classical music, it's flawed to the point where it actually seems designed to fail.
I stop to listen to buskers -- but not when I'm moving through a crowded station on my way to work. It wouldn't matter what they were playing or how well they were playing, I'm on a tight schedule and keeping my job is more important than even Bach I'm afraid.
I wonder if Joshua Bell stops to listen to buskers when he's running to catch a flight to his next concert date?
They should have put him in a shopping centre on a warm Saturday afternoon.