In my opinion, this is absurd to the extreme. It's not the resturant's fault for serving an obese person what they knew better than to order. The resturant is simply doing what it's there for, providing a meal for a hungry person, regardless of hungry person's weight. Obese people, imo, cannot blame a resturant for making them
fat. They could have ordered a side salad instead of the onion rings. It's not rocket science. Some people, unfortunately, have a proclivity for blaming their problems on anyone but themselves.