Just saw this in the Orlando Sentinel. I can see renting them poolside (and have) but I'm not so sure about this.

The theme park will soon start renting cabanas for almost $700 a day.

The private, shaded cabanas near Space Mountain in Tomrrowland hold eight people. They are available for the entire day and cost $691 with tax. Rental includes lockable storage, charging stations, sunscreen and insect repellent, water and soft drinks, and food.
Other sites are reporting that the food included in the price is fruit and one Mickey bar per person. Food delivery service will be available but at a charge.