(I work for an up-brand mass-market chocolatier. The company has café stores and non-café stores. I was the head barista for two years in a café store, but at this point I am a senior sales in a non-café.)
Guest: “I bought your hot chocolate and I don’t like it.”
Me: “I’m sorry to hear that, sir. Can I ask how you’ve been making it? That sometimes affects the taste.”
Guest: “I’ve done it every way. Whenever I come in they tell me something different.”
(I list the ways you could make it and he nods along, the response being, “No, I didn’t like that way.”)
Me: “The only other option, sir, would be to use a pressure wand, like a milk-foamer on a coffee machine.”
Guest: “That’s ridiculous! I’m not forking out money for a product I’ve already bought!”
Me: “I understand, sir, but there isn’t any other way I can think of to help you. If you have the product or the receipt, I can refund or exchange.”
Guest: “I don’t want to do that! Can’t you just make it here?”
Me: “This isn’t a café store, sir; we don’t have those facilities.”
Guest: “Well, what are you going to do about it?!”
Me: “If you have the receipt or the product, I can give you a full refund. Other than coming to your house and making it for you, there’s nothing I can do at this juncture.”
Guest: “Come to my house, then.”
Me: “Sir, I’m not prepared to do that. I—”
Guest: “You clearly don’t care about your job, then!”
(He stormed off. Apparently the same guest comes in about once a month and complains about not liking a particular product, but never buys anything in-store or has the product or receipt. Some people just like to complain.)