Well that is what is done in Italy (and coffee shops here since a lot of them use Espresso machines too) to make the" long" coffee expected in the US.ok, I don't understand why you would dilute a nice espresso with water?
Very few Italian coffee shops that I have been in have a filter machine so anybody wanting more liquid will get hot water put in a double Espresso to create it, same in my local coffee shop, milk will probably be offered to put in it as well. This is called anm Americano.
In Italy typically one would get a glass of cold water with the espresso for thirst quenching purposes.