nasty_khakis said: "Yes, it's fairly intentional, especially when they can easily reconfigure a row or two and add a couple of seats to quality a "broadway" house.
They do it to save money. You don't have to pay as much rent, you can pay actors/crew/musicians a lower salary generally, etc. They get almost a broadway level capitalization of 499 seats to sell but pay close to have as much in running costs."
You're correct in concept but off in the details. Rent isn't determined by the number of seats, it's determined by the landlord. And it's not an actual lessor/lessee relationship. The producer is licensing the use of the theatre, not entering into a lease/rent agreement. Also, capitalization refers to the money being raised, not the number of seats.