Ugh, as an americano drinker I'd be annoyed as hell by this. I have a 52oz water cup at my desk, for me much of things is about the quantity of liquid so I dilute everything. I get my alcohol drinks heavily cut with mixers so they last longer. If drinks are small I finish them way too fast. So a tumbler of a mixed drink lasts me 8 minutes but the same drink in a pint with little ice and more mixer is more like 40 minutes. One leads to shitfaced quick and is a nice buzz. Same for coffee. Sitting at my desk with a small drink I'll finish it without noticing I'm drinking it. 20 oz coffee with the same # of shots and It'll take 30 minutes to finish and I'll actually notice and enjoy it.

I'm an adult, I can pay attention to what I order, and I'm not embarrassed to order things that are not directly on the menu. I'm tipping the bartender and the barrista so they make it the way I want it anyway.

Coffee in Italy, France and other places in Europe is meant to be drink in small cups. Like a shot. I've asked for Americano in France and people are always making fun of me. But I will never understand why you would drink a shot for pleasure when a drink can last way longer. So yeah totally agree with you.

This varies a lot within Europe. In the Nordic countries, the norm is to drink larger cups of coffee, traditionally brewed filter coffee, but lately also various latte/etc. type drinks (overall, similar to what Americans drink), slowly over a longish period of time. That's embedded in cultural expectations as well: going out "for a coffee" is a popular type of casual socializing, and means sitting at a table and chatting for maybe an hour or so while you sip a coffee. Not the Italian-style 30-second outing, where you drink a shot of espresso at a bar standing up.

There is an Internet meme going around that purports to show a German serving size one step larger than extra-lage, called "American." I have no idea if this is real or not. Can any German/European HNers confirm or deny?