I don't think most fats have an actual eating disorder, but I suspect many engage in disordered eating. There's no way they're just eating until they're sated when they're eating 4k calories a day... so what are they doing, and why? I think they're using food the way an addict uses a substance. It's not at all the same as anorexia (and I'm sure fats are especially disgusting to someone who struggles with anorexia) but eating that much is sure as hell disordered. That said, "fatorexia" is an incredibly poor choice of words.