I spent two years in a rough-ish public school. It was the hardest period in my life but it taught me very much about valuing people from all walks of life and especially on adapting my behavior to get positive outcomes in any social setting. I can absolutely see how that experience is lacking on some of my friends that spent all their lives in protected environments.
Fair point but can't that be worked around through having parents teach their kids to value people from all walks of life? True the lack of exposure does play a factor but I would wager it falls heavily on what parents hand down to their children and how they perceive the world.