The Rockies are a cash cow. It would take an obscene amount of money for the Monforts to sell the yteam.
My wife and I, in the past, regularly attended 6-12 Rockies games per year. The games are an occasion for many, fans from all over the midwest. They simply want to see an MLB game with their friends.
What may change this scenario is the deterioration of downtown Denver. These fans usually stay for 2 nights in the city.