Mafiosi signal protected status through cars visible to thieves.

Evidence

Car theft is no laughing matter for the mafia. How, after all, can a mafioso signal that his car alone is untouchable among a thousand others? Were he to resort to a warning label, say with an M on it, so could anyone else. If he were to display somewhere on the vehicle his (less easily pirated) surname or his even more resonant nickname, he would forfeit the advantages of anonymity. One solution might be for him to leave the car unlocked, relying on the fact that in high-crime areas this would signify an intimidating lack of fear (Calzetta says that his boss left his car unlocked). A more extreme alternative is to drive a small, unassuming car, which is less likely to attract thieves; and indeed many mafiosi do own such cars. But perhaps the most theatrical solution is to buy a flashy foreign car—a black BMW, cream Mercedes, or red Range Rover (all real examples)—which transmits an unequivocal message to the thief. This gambit accounts for a notorious preference among mafiosi for showy cars, which is usually attributed only to the desire to impress. — Diego Gambetta, The Sicilian Mafia The Business of…, 922

Categorization

• XREF: Directly extends Gambetta’s core signaling thesis from the earlier chapters: the flashy BMW is a costly, observable signal analogous to the Godfather-bond and informal reputational mechanics also visible in Milgrom et al.’s private-judge model. The car is a visible enforcement proxy — a claim on protection — readable through Schelling’s commitment signaling.
• SEED: Article angle: ‘costly signaling’ in the Godfather films — how flashy cars, horses’ heads, and public displays of loyalty are all Garfinkel-style commitment devices, not mere vanity, mapping Puzo’s world onto signaling theory.
• ADDENDUM: Pairs with ‘Grafting & Growth’ inversely — where thorns are defense-signaling in botany, the BMW is defense-signaling in the Mafia; the anonymous care demanded for trees maps onto the careful anonymity of the mafioso’s car.