I wouldn't use it as my only resource, but I thought it was pretty reasonably priced in the parks, all things considered. We didn't buy it at the resort, so I'm not sure about pricing there.
We would feed DS in the room each morning, stop by the babycare center to get some food for him (I don't remember the selection being huge, but it was fine for us), usually buying enough for his midmorning snack and lunch at the same time. We'd carry an empty sippy with us and refill it with bottled water for him to drink between nursing sessions. Depending on our evening plans, we would either take food with us to the restaurant or buy it at the babycare station.
If you won't have access to a car, how about sending baby stuff to yourself via UPS?