This seems very dishonest to me, and if I was a random walk-in customer of that coffee shop, I'd feel cheated. I have absolutely no idea how many ounces are in

This seems very dishonest to me, and if I was a random walk-in customer of that coffee shop, I'd feel cheated. I have absolutely no idea how many ounces are in a "medium" at any coffee shop, and I don't want to know. When I ask for a medium, what I'm really saying is, "please give me a reasonably sized cup of coffee, not too big, not too small." If I'd have asked for a medium and gotten a super-jumbo-medium handed to me, I'd have felt manipulated in some vague way--as if the big coffee shop knows damn well what a "medium" is, and they know damn well that that's what I want, but they're going to give me their own special interpretation of a "medium," which is more coffee than I want, and also just so happens to cost $1 more. Fuck that, and too bad you didn't mention the name of your chain so that I can try not to visit.