Nice song, and interesting message, however I'm not quite sure if I agree with what your getting at.
To put things bluntly video games are generally about exceptional and fantastic situations. As a result people involved in them as heroic protaganists are going to represent specimins of humanity capable of dealing with those situations. To put things into perspective some fat boy, is not going to be able to run and gun terrorists and such. A special ops guy though is liable to be EXTREMELY fit, and in general fit people tend to be rather handsome at least on some level.
This is not to say that an "everyman" protaganist can't work, it can and has been done occasionally, especially in adventure games and the like. However such stands out by being an exception to the rule, and typically requires a plotline written specifically around it. Such characters also tend not to remain the everyman after a certain point as they adapt to whatever they are doing. For example your rotund dude is going to stop being rotund when he spends six months in a jungle fighting zombies or aliens or whatever... assuming he survives of course.
Not to mention the whole issue of escapism, while you might disagree personally (and let's be honest, your cute and talented) most people want to get away from reality to an extent, and that's the entire point of the idealized forms and situations.
I notice a lot of pics of Dead Or Alive Volleyball games, I could write a ton on the DoA girls alone (from a number of perspectives related to this), but consider also that the premise typically involves them being invited to that island because they are world class babes. I doubt it would be as entertaining or sell as well if someone was to make a game about inviting a bunch of fatties and skinny nerds to an island.
Well at least not entertaining the same way, I suppose you could make a humor game out of a weight loss/health island with all of these ridiculously overweight and skinny/weak people trying to work out and failing. Cruel yes, but to quote "The Hangover", "It's funny because he's fat!". Of course as a fatty myself today, I admit I feel more shame than I should over such things and finding them funny... though I can still appreciate self-depreciating humor.