AFAIK the body processes HFCS and sugar pretty much the same. The difference is, HFCS is almost always a mark of a more highly processed food, and more highly processed foods are going to tend - on average - to be more junk food-tastic, and going to tend to have other highly processed ingredients that can contribute to binging.

Maybe you're more satisfied by the taste of the sugar (vs HFCS), and over the course of the rest of the day eating a little less of other stuff. But as far as I've read, the link between HFCS and obesity has more to do with the fact that - if you're eating more HFCS than average, you're necessarily eating more processed foods. The body does process different sugars (fructose, sucralose, etc) slightly differently, but the difference between two full sugar sodas (even if one is HFCS and the other is cane sugar)... with likely identical calorie counts (both coming from simple carbohydrates)... well, it's likely to be a placebo affect more than some magical property of cane sugar.