BJR said: "I think it's also a question of target audience. Most New Yorkers are going to avoid something if they think it's aimed at children and families, that they'll be surrounded by noisy kids in the theatre. And frankly, from the time I went, that's not untrue."
I disagree a little bit with that statement. Granted, the cost of attending a Broadway show is often high, especially when you're trying to get tickets for your family and that includes one or more children. But the goal of creating content that can attract children and families with young children is a worthy one. Don't we want to introduce children to the theatrical experience? (The 'noisy kids' concern is a separate question of etiquette.)