I was visiting family and we went to a restaurant in NC that did this and the waitress just shrugged and said "We are environmentally friendly, we don't have paper menus. Borrow someone's phone" and then walked away.
Questions I didnt get to ask... Like how much environmental impact does a dozen menus have? Also before you walk away... can I borrow your phone? I am not asking some stranger for the phone.
My sister ended up having a smartphone with her. We wanted to leave, but my mom wasn't having none of it because "it would be impolite, they have already served us water".