the plumber – i know exactly what they meant. They have 3 levels. Not recommended – i.e. not kosher. Recommended, but relying on certain leniencies, i.e. kosher m’ikur hadin. Regular coffee falls into this one if I recall correctly. And recommended l’chumra. Espresso falls into this one, and if I recall, the reason is because the espresso machine is not washed with other keilim. So a plain espresso poses no problem for anybody. Unless you put in milk, then it’s just not cholov yisrael.
So, with no stretch of the imagination, you can be dan l’kaf zechus that people are either getting regular coffee or espresso.