There's more to it than that. I was lucky enough in China to encounter a vending machine for fresh orange juice. The machine included a press; you could watch whole oranges roll into the press and juice flow into the cup which was ultimately dispensed.
This is great as a novelty, but the juice you got was only very slightly more flavorful than water. No one is going to drink the juice of 8 oranges. What we drink is heavily concentrated, with vastly less water than would have been present in the fruit.