Supply and demand. In this case the supply is small (limited acreage, vertical, etc). Demand is high....your located dead center of the highest concentration of people in the country. East coast resorts have distance from civilization factored into the cost. A season pass at Jay Peak is not so expensive, despite being the best mountain for 2 thousand miles.
I agree demand is high, but supply is quite high as well. Windham, Hunter, Belleayre, Mountain Creek, the Poconos resorts, the Berkshires, and Southern VT all add up to about 15+ resorts within 3 hours of NYC. I guess to your point though you then start bringing in Boston, Philly, etc.
I am more speaking of the local places. Why would I spend $1k on a Windham pass when I can drive an extra 1-1.5hrs and be at mount snow for the same price? To me there is a clear difference in the product (terrain, size, snow, amenities, etc) that far outweighs the extra time in the car.
I guess I really wish I was just out of this area. Next year will probably be like this year. 18 days on snow at 9 different mountains (Hunter, Windham, Mountain Creek, Belleayre, Mt. Snow, Killington, Breckenridge, Blue Mountain, and Wildcat.)