On the political weaponization of food-taboos:
Food taboos are obviously an ethnic marker, but by itself that observation explains nothing. Why do people wear ethnic badges to begin with, let alone a costly one like banning a source of nutrients? The social sciences assume without question that people submerge their interests to the group, but on evolutionary grounds that is unlikely (as we shall see later in the chapter). I take a more cynical view.
In any group, the younger, poorer, and disenfranchised members may be tempted to defect to other groups. The powerful, especially parents, have an interest in keeping them in. People everywhere form alliances by eating together, from potlatches and feasts to business lunches and dates. If I can’t eat with you, I can’t become your friend. Food taboos often prohibit a favorite food of a neighboring tribe; that is true, for example, of many of the Jewish dietary laws. That suggests that they are weapons to keep potential defectors in. First, they make the merest prelude to cooperation with outsiders—breaking bread together—an unmistakable act of defiance. Even better, they exploit the psychology of disgust. Taboo foods are absent during the sensitive period for learning food preferences, and that is enough to make children grow up to find them disgusting. That deters them from becoming intimate with the enemy (“He invited me over, but what will I do if they serve… EEEEUUUW!!”). Indeed, the tactic is self-perpetuating because children grow up into parents who don’t feed the disgusting things to their children.