Let's imagine this case scenerio and what to do in such situation. Imagine you are in a street and very hungry and there is only one place food is being sold in that area. You go in to buy food but some how the seller have a rant with you while still holding your food in his hand. Don't say "an hungry man is an angry man" then fight back. Since you need the food, keep your cool, pay and collect your food. You can responde afterwards if you want to because you have your food with you now. The one who holds the food have the upper hand.