Also from experience in ED recovery (I didn't have anorexia, but many in my group did) there's a huge element of perfectionism involved in anorexic behavior. As you said it has to do with feelings of absolute control.  I think OP here is onto something but from the wrong perspective. I would definitely say most of the morbidly obese have an eating disorder of some kind but I think it's more of a binge-eating disorder. Of course, no one wants to admit that they binge or even overeat so it's no surprise they go to extremes denying this, just like an anorexic goes to extremes hiding their own disordered eating.