A minor point: Banfield's study found amoral familism not in Sicily but in mainland southern Italy. Banfield states that Montegrano is in the province of Potenza, which is part of the Basilicata region of Italy (Moral Basis of Backward Society, pp. 1-2). Basilicata is known as the instep of Italy.
It's a great book and I'm glad to see it's still recognized.