We rented a stroller last time - younger DS was 5 and in Kindergarten at the time (and I have been told on here that kids that ride in strollers past a certain - very young - age are lazy, obese, and spoiled, just FYI) -
Laughable, since DS is none of those - he is 7 1/2 now and weighs 45 lbs! And is in his 3rd season of tackle football where he practices 2 hours/day five days a week, swims, and has played soccer and basketball. Oh...and runs around outside all day long and plays pretend football games with himself and the couch all evening long LOL (he is the QB and the receiver, and the couch is either the defensive line or the end zone LOL).
BUT....he does get horrible, painful leg cramps that really can impede his walking for up to 1/2 hour at a time. They happen randomly and often in the early evening. For that reason, we rented a stroller. Honestly, he never even really used it - maybe once or twice going from one end to another. But it was awesome for holding our stuff so that we didn't have to go all the way up to the front of the park everytime someone wanted a sweatshirt or a drink of water from their water bottle!
We parked the stroller in each "land" at MK, did everythign we wanted to do, then retrieved the stroller and moves on. I loved it, and would really consider doing it again even though the kids wouldn't really need to use it.