The food and wine kiosks take the
DDP on your Key to the World (KTTW) cards. And yes, if you have charging privileges tied to your card, you can charge them back to your room.
However, the kiosks also can take the Disney Rewards "debit" card if you want to eliminate the middle man. If you decided to charge back to the room, you would need to settle up at the front desk before you check out, applying your Disney Rewards card there.
And the most important thing I would do if I applied the Disney Rewards against my room charges: Ask for an updated "folio" of the room charges to see if the Rewards were applied to your total and a new balance remains.
The hotels can make mistakes, and it's better to double check while you're standing there than to be surprised later when all charges are applied to your credit card in error.
I personally liked using my Rewards card at point of service, and the receipts had the remaining balance of Rewards for each use.
