Society, man. Over half the people you run into everyday, at least in the United States, are clinically obese. One of my favorite authors (Stendhal) said "the curse of our age is that even the strangest aberrations are no cure for boredom," hence why they put Whitney Weighmore on TV and why disgustingly obese people don't seem abnormal to most people. It's like boiling frogs, if you expose people to unnatural shit for long enough, they won't think anything of it.