I can understand the annoyance.
Most children under 6 (and some even over) can't sit through a 90 minute Disney film. They need potty breaks, snack breaks, attention breaks, etc.
I can only imagine what they'd be like during a 2 hour musical on Broadway and how distracting that can be for the patrons around them.
When you've paid $100+ for a ticket to see a Broadway show I don't blame you for being annoyed if there are tons of distractions around you.
"All our dreams can come true -- if we have the courage to pursue them." -- Walt Disney
We must have different Gods. My God said "do to others what you would have them do to you". Your God seems to have said "My Way or the Highway".