Disney is feel good fantasy where everyone finds true love and lives happily ever after. The lovers tend to be from different worlds/classes (e.g. Beauty and the Beast, Aladdin) but since they were meant to be together, these things didn't matter. Fats want to believe that sort of thing can happen to them, where they have some soulmate that will love them no matter how shitty of a person they are. I guess they just hone in on that one part and neglect to realize that all Disney characters are also attractive and good people...