2. Pointing out that Starbucks is more expensive than any other coffee

That Starbucks is expensive is a fact that is embraced all over the world. The baristas know their coffee is expensive. All the Starbucks bosses know their coffee is expensive. Heck, even the homeless do! If you’re going to launch into a tirade about how a venti frappuccino a day for a whole year is equivalent to a secondhand car, feel free to show yourself the door.

3. Getting into a cup size fiasco

There is only a finite number of times that a Starbucks barista can give a lesson on the sizes of their cups, so read closely: tall measures 12 ounces; grande, 16 ounces; venti, 24 ounces; and trenta, 31 ounces. Save your confusion for somebody who cares and is not in a rush to take orders.