Feels like that merchant boy broke quite a lot of rules of etiquette there (physically grab a woman, tell ppl she would give them cold water without her permission, not negotiate her wage before starting to sell her services without her permission, setting the price of the beverages without negotiation (hopefully she asks for a wage at twice the price per beverage), if not outright laws (physically grabbed a woman and detained her against her will. Especially since she seems to be part of the ruling caste?).
Here's hoping he gets screwed over when she demands payment. Thought he likely won't.
edit: aw, seems he didn't get screwed over.