Maybe the op should try a spin on that sort of restaurant, have a healthy menu place, where the over 400 pound people can eat free, give them a chance to try some healthier options....
Spoken as a morbidly obese person, who isn't stupid, but does find food addiction worse to kick than smoking, stopped that one 4 years 5 months and 30 hours ago according to my quit keeper, but sigh I keep eating, if only I could go cold turkey