Every instinct tells us to stick to what we know, surrounding ourselves with like-minded people who have experienced similar upbringings, usually within the same culture. It’s hardly surprising that when one community ups sticks and immigrates to another, often alien area of the world, there is a real propensity to form clusters, creating communities that are full of people who share the same (or corresponding) backgrounds. It constructs a home-away-from-home feel, and aids the adjustment to different societal expectations, while still allowing the preservation of one’s own, cherished culture. In a way, that’s what the mafia and other gangster communities are.