IIRC, back in the "beatnik" era, when coffeehouses began to proliferate, the term "expresso" was commonly used. I think it was merely an Anglicization (Americanization) of the Italian word.

It was not until I visited Italy in 1971 that I really noticed the Italian word "espresso." While I prefer using the Italian word (since I learned to speak a little Italian), at the same time I can see the switch from "expresso" to "espresso" in the US as a bit of an affectation, the trendiness characteristic of expensive coffee shops where nobody drinks "coffee," they only drink "latte," "mocha," "espresso," etc.