I personally frown upon smoking, too. It's a drain on our healthcare system, just like obesity, and inevitably is one reason premiums continue to rise. I don't think it's discriminatory to feel this way, either. For most overweight people or smokers, it was a choice they made and something they can control (I realize some morbidly obese people actually have a disease which makes it sometimes impossible to lose weight), and everyone is free to judge others based on choices they make. I say this b/c I used to weigh 240 lbs., made a choice that I no longer wanted to live like that, and lost 70 lbs 5 years ago...and have kept it off. So I don't really think it's classless to frown upon an individual who weighs 300 lbs and is eating two combos at a Disney CS restaurant. I don't feel sorry for them, though. They made a choice and I don't think they want anyone to feel sorry for them. I, however, do think their behaviors (stuffing their faces with tons of food or smoking) are disgusting. And it's my right to feel that way. I also think murderers and rapists are disgusting people.
Back on topic, I can see the appeal of this option for some guests, and at the end of the day, I think it would generate profits for Disney, so why not try it? It is almost sick how it could be set up, though--lines at CS locations are long and the only people who would really benefit from this option are people who would want 2 or 3 plates of food at a single meal...meaning they would have to stand in those long lines 2-3 times in a short time period. I don't know many 300 lb. people who would want to stand in line that much...and that could be Disney's best deterring factor to people cheating the system and feeding their entire family: only have this valid at the most popular CS locations where it's not very practical to stand in line 6 times in a row to feed your whole family. You'd be at Pecos Bill's for about 3 hours!