While it's conceivable this is the way Universal is placating Coca Cola (for not selling Coke, Sprite and Minute Maid inside WWoHP), I personally believe Butterbeer and Pumpkin Juice are being made on property in the Production Kitchen, especially knowing Steve Jayson. He's extremely controlling, protective of his operations and prideful; knowing he crafted the recipes, I wouldn't be surprised if he wants to keep production in-house. The PK/Bakery is certainly large enough to handle the production; it is the length of a football field, as is the warehouse attached to it. There are 6 1000 Gallon Steam Kettles they use to make all soups, sauces and such used in most of the restaurants on property, as well as several "Smaller" kettles. They have a bagging system attached to the kettles to quickly and cleanly bag these liquid mixes. The "specialty" mixed drink(s) you can get in the refillable souvenir cups at HHN- yeah, they make massive batches of it every day and store them in 5 gallon bags. I could definitely see the ability to add additional equipment onto the existing system to bottle the pumpkin juice.