I think that it is important to know a few things about self-esteem. First off nobody can clearly define what it is and person who did define Albert Ellis has shown that the concept self-esteem is toxic. Fat girls have high self esteem and that accounts for why they can throw so much fattitude and are generally such a pain in the ass. Fat girls have big fat egos.
Skinny girls are humble and lovable not to mention that they look and smell better than fat girls. While fat girls are generally sluts and since men like sluts their sluttiness comes with too many minuses and not enough pluses. A dis-inhibited slut is every man's dream but when you add fattitude, histrionics and chronic yeast infections it really begins to suck.
A lot of guy like it when the woman is on top in either cowgirl or reverse cowgirl position but that position with is not only impossible for if the guy is fat it is also downright dangerous. And who wants a yeast infected fat girl sitting on their face?
Now for some comparisons.
What would you rather do bone a skinny chick or pork a fat girl?