Taking a small bit of a stretch, eating a lot of fatty food does affect others.
It affects your job, where your lack of good health will cost in productivity as you're out sick a lot, forcing others to pick up your slack, and costing the company money to reimburse those people.
It affects the people of the nation if you (as many people of ANY weight do) rely on the government for medical care, since your completely preventable health problems are now costing the taxpayer money.
It costs me, personally, because I don't want to see Carly Wilson's god-damn stomach stapling but there it is and God that's nasty. Why, ET, why did you have to flash the pictures? *sob*
Keep in mind that I think the idea of regulating fat in food like this is stupid. Make sure that people are provided with accurate descriptions of what's in food, and let them decide themselves. But these are all arguments that I can see being used to try and convince congress to pass laws regulating fat anyway.