It's no secret that fat guys prefer skinny chicks and are repulsed by fat chicks. Most men find fat chicks repulsive. I am one of those men. It's not just their unsightly blubber that makes them so undesirable it's their behavior. Gluttons are fun but too many fat girl gluttons are a pain in the ass.
The other reason fat guys are into skinny chicks is purely pragmatic. It is either mechanically difficult or impossible for us fat guys to pork a fat girl even if we wanted to do so.
Fat Bastardo's Gallery of Gorgeous Gaunt Thigh Gap Girls