The vast majority of improvements made to neighborhoods come from financial incentives. People aren't opening new shops and restaurants and businesses for the heck of it, they are doing it because there is money to be made when people with higher incomes move there. If people with low incomes all stayed those things wouldn't open because there wouldn't be money there to support them... And in terms of improvements to the houses themselves, a massive number of those happen because they see the neighborhood growing and think that they can buy low then eventually sell high. Even of people who are just improving and upgrading things because they want to have improved things, a whole lot wouldn't do so if those improvements weren't reflected in the value of the house. Spending $100k remodeling your kitchen and bathrooms makes a lot more sense when it increases the home value $80-100k. Not nearly as many people would do it if it was just a sunk cost that you never recouped.