Well for the most part, shows are financial failures - so they don't. But for the successful ones, the sale of more expensive tickets makes it possible - particularly when we are talking about heavily, heavily discounted tickets such as rush seats etc. or lottery tickets etc.
Of course, that doesn't mean smart producers shouldn't set or adjust the pricing appropriately to account for supply/demand, within reason. But I just feel we need to keep in mind that this is an expensive business and the only way it will be sustainable is if people do actually pay a reasonable sum for it.
I feel conflict within myself sometimes - for example, I bought a rush ticket for Bridges of Madison County. I loved that show, but at the cost I paid for it I did nothing to help it survive financially.
Give me claws and a hunch, just away from this bunch.