Yes, it's really the quantity that's the issue. It's very easy to drink a lot of juice, because it is good. The variety message gets lost. You identified your seven oranges. Well, eating seven oranges is not really variety, so that wouldn't be a recommendation either.
Really, I think the concerning part is the quantity. As I think Dr. Critch would agree, young children especially might drink a lot of juice instead of just drinking water if they're thirsty.