I just saw someone order "two Americanos" from a place that also, for 70p a cup less, sells filter coffee. Why?
Caffe Americano is an international insult disguised as a beverage. It means "just keep adding hot water to the espresso until it tastes like that filth the Americans drink"; compare (someone else's example) assiette anglaise, which means "well, cold meat is all the English eat, isn't it?"
So, is there a reason to have someone make you a slow, expensive espresso and then try to turn it into a filter coffee, when they could just pour you a filter coffee? My palate for coffee is lousy, so this is a genuine question; for all I know the Americano tastes much better. But it seems more likely that the order would be made on the assumption that nowhere one would want to order serves filter coffee anymore; or that if somewhere does, ordering it would put one outside the circle of civilised people.