One function of etiquette, and perhaps one of its earliest documented forms, at least in Western Civlization from the Middle Ages onward, was to distinguish the rich and titled from the poor. This became especially important after the the collapse of feudalism, when nobility and wealth no longer automatically coincided. In order to tame the pretensions of the nouveaux riches, aristocrats surrounded themselves with a strict etiquette which no person risen from the people could learn without years of study (aristocrats generally had childhood to learn all this). Many of the "manners" that we take for granted were invented precisely to distinguish those in the know from the ignorant.