The WORST service is at places like this. I want to assume the expertise and competency of every person I interact with. Especially in the service industry. The best service I get is terse, direct, and professional. I don't need my fucking barista to pretend they like me. I need them to get through the 15 fucking orders before mine in a timely fashion so I can get on with the rest of my day. And if some dickhead doesn't know what a machiato is, he can get his happy ass to the back of the line and order it again.
Barring allergies or medical issues, shut the fuck up and move on. If getting the wrong coffee is the worst thing to happen to you in a day you're living a pretty charmed life.
But then again, I did get fired from Starbucks as a teen.