Stallholders are eloquent orators, using body-language to convince listeners.
Rhetoric is the art of discovering the available means of persuasion(Aristotle).
Pleasant how this is expressed in many languages each with their colored aspect of the notion like the Latin "Captatio benevolentiae" or the German "Umwertung aller Werte"(Nietzsche) ... indicating each a more particular way of persuasion (reason, emotion, coercion, deception and so on ...) and we use them all daily, often unconsciously !
Seen on the market of Nevsehir under the colored parasols.
PS
you can refine your capability of persuasion reading more of 'how to' on Wiki