It's very true that New York City isn't being affected by the financial crisis but it isn't just because wealthy people live here. Perhaps the biggest reason is that 80 percent of New Yorkers use the subway to get to work and don't own cars. I'm not wealthy but have been able to keep my quality of life because I don't have to spend money on gas. Because of this, more and more people from the suburbs are moving into the city and realizing that the money they were saving by living far away from work is being erased by the high cost of gas and commuting. You're right, there is no way Disney would vacate this city. They picked 5th Avenue originally because it was the cleanest most Disney-esque part of Manhattan and Times Square was a dump. Now (thanks in part to Disney themselves) Times Square has become a familiy friendly tourist trap so it makes sense they would want to be there. 5th Avenue is where Prada and Tiffany belong, not Disney.
I actually watched a financial program years ago that questioned people who move from cities to the suburbs because of its cheaper real estate. The expert was advising people to guage their costs, because their housing cost-savings could be overshadowed by the increase in commuting costs and other types of costs. Whats the point in saving $300 a month in housing when your transportation and other expenses increase $400? New York is almost too big for its own good. The reason NYC isn't really affected is because most middle class people can't afford to buy a house, so most are renters (who are being pushed out by the wealthy even in Harlem). Brooklyn isn't even affordable and the Bronx is getting more expensive as well. The people who own property have more than enough money, so they can weather the storm. New York is a crazy expensive place to live. But it's totally worth it!
That said, Disney's current location is definitely not tourist friendly, and they should have kept the store in Times Square...it was starting to turn before Disney was a large presence.