I have a sweet tooth and yes, I weigh more then I should and I don't care. I'm 54 I don't expect to be thin at my age. If I want to eat something that is fatty, a "fat " tax is not going to stop me.
The cost of healthcare is already out of control due to today's technology - not because people are heavier. If the government wants to enforce a fat tax, they should tax the companies that add fat to their products. Perhaps then companies would change their recipes and waist lines would start shrinking.