Cities are not stagnant communities. They undergo continuous growth and change. No community in Manhattan can claim to be unchanged for as little as 10 years. Communities are microcosms of cities. They are affected by the same influences that cities succumb to.
Economies rise and fall, employment is sparked and crumbles.
With the cycles of success and failure come different waves of residents. If the downtown area begins to take on the culture of the students who live in the area, it is not any different than if the area took on the culture and image of other migrating residents. Community members and area residents should consider and keep in mind both the benefits of having NYU students in the downtown area as well as the natural tendency towards toward change before they draw up and issue complaints against the university and its students.