As as a side comment: I have personally witnessed the weirdest reasons people narrate to FAs and gate agents to get something better inflight. The most memorable one was 'I have bolts in my spine so I have to sit at a window seat to rest my head on the wall'. I'm certain airline staff hear such fake reasons on a daily basis and develop a defense mechanism for it. Hence my my recommendation upthread to always formally notify the airline with details of the disability. The information ends up on the manifest mainly so FAs are informed of the impact on evacuation procedures and the like.