Yesterday, Tim Harford posted an excellent article for Slate: Starbucks Economics – Solving the mystery of the elusive “short” cappuccino.

Many may not know this, but Starbucks offers a short cappuccino that can be readily ordered at just about any of their forty zillion locations. However, you’ll never find it on the menu. And the dirty secret? It’s both superior and cheaper than the bathtub-sized offering they list on their coffee menu.

Why is it superior? For one, it’s vastly superior to their “regular” cappuccino because the highest quality microfoam you can make does not produce in large volumes. You have to skim it from the frothing pot of steamed milk. The standard Starbucks cappuccino, being so gargantuan, requires any shape or form of steamed milk just in order fill the oil tanker-sized cup. (And this says nothing of your tastes for a cappuccino with more or less espresso in it.)

Why is it not listed on their menu? Because of the economics of serving beverages. It’s the same reason why movie theaters want to upgrade your “medium” 24-ounce soda to the gallon size for an additional 50 cents. The profit margins are much tighter on cheaper items, so the bigger the price tag, the better the cashflow. Even if it costs a few cents more to sell you something that much larger, the additional ingredient costs pale in comparison to things such as rent, barista salaries, insurance, utility bills, and business loans.

Well, that and this is the nation that invented the 46-oz Super Big Gulp®, afterall.

So the next time you find yourself in a coffee wasteland with a jones for an acceptable cappuccino, ask the nearby Starbucks for a short cappuccino. You’ll get a far better beverage, and you’ll even save a little pocket change in the process. And tell them TheShot sent you.