What about my comment implied I didn’t realize that? Anyways, Raktajino was also consumed a lot on Voyager. Its strange that Quark focused on Root Beer in light of all the other stuff people drink, other than, hey, this is the only carbonated thing they drink that’s not caffinated or alcoholic … but that wouldn’t be true either?
He did say “Starfleet” drink a lot of it, not “humans”, so maybe it is just that pupular with Vulcans, Andorians, Tellerites, etc.