Question about Population Density

Unlike other species, human reaction to population density is mediated by attitudes and cultural definitions about how many are too many. A dense population is one thing in a culturally homogenous city where few are poor, and there is a culture of civility (like Amsterdam). But a dense population is quite another thing where many are poor, culturally dissimilar, and there is a weak culture of civility. What do you think the American experience of growing populations will be? On a small scale, think of the times when you have lived in a dense environment with others (for example, a shared apartment, college dormitory or military base). How would you describe that experience? What kinds of special rules emerged to deal with problems of crowding? Not all rules deal with population density problems, but many do. In American cities, how do wealthy people deal with problems of urban crowding and congestion? This paper should be two- to three-pages.