No, this is ridiculous. If you want to get around the park without physical effort or are incapable for whatever reason then a wheel chair or ECV is plenty good. If the trouble is being seated, then what do you do on the rides? As others have mentioned this would be dangerous. Also they can't require proof of a disability, so I see this being abused and a huge amount of people choosing to use a Segway. Because unlike a boring Wheelchair thing Segways are fun.