They genuinely think that being fat wouldn't suck in a vacuum. They think that all the bad aspects of it are due to social stigma. If they fixed everything and put fat people on all the billboards and in all the movies and if everyone wanted to date fats, their knees would still hurt, they would still hate themselves, and they would still die at 45. They are fighting a battle against evolution. Pretty much every social movement currently in a nutshell.