Kevin Drum and Philip Boroff shouldn't be surprised that the five full-timers on the Carnegie Hall stage crew are making $400K-$500K. Of people making big money in New York there are far greater absurdities.
If you're running Carnegie Hall, you'll be ready to hire the best damn carpenters since 33 AD. They'll want enough money to live very well in New York, so you give it to them. Huge stuff happens there, and you want to make sure it doesn't screw up.