Oh, man, so many ways you can piss off your Barista:
1. Talk on a cell phone while ordering, especially if you just mouth the order instead of saying it out loud.
2. Leave garbage on your table.
3. Leave garbage on the condiment bar INCHES AWAY from the garbage hole in said bar.
4. Order a macchiato and then get mad when you get espresso and foam. That's what that drink is! A caramel macchiato is a drink that Starbucks invented, and it’s just a vanilla latte with a bunch of caramel sauce. So if you want that, that’s what you have to order, IN STARBUCKS.
5. Order an espresso in a big glass of ice and then go and make yourself a latte with the milk from the bar. Look, if it means that much to you, I’ll just charge you for the espresso and give you the latte. At least that way I don’t have to refill the milk at the bar every time you come in the store.
6. Look, you spilled something. It happens, it’s ok. I may even decide to give you a free replacement if I like you. But you’re not entitled to one. You bought the drink, you got the drink. Nothing about the transaction guarantees that it’s going to end up in your stomach. I’m not sure why you think that the fact that you just made a mess that I have to mop up entitles you to a free drink.