I tell dudes, fatties get wetter and will do anything to make you happy. Now im talking about FAT girls. Thick girls are definitely datable/wife material, but if you want some down and dirty nasty sex (spitting, choking, pissing, etc), get you a whale
I have no trouble getting skinny girls wet 'down there'.
Are you sure you aren't confusing wet and sweat?
As for real chunky girls doing anything - I do recall in my college days that not only did the more rotund girls do anything you asked but they also had a tendency to suck the shit out of your neck whilst fumbling. I never did find out if this was to intentionatlly give you what we Brits lovingly call a "love bite" to mark their territory or if they just got hungry during sex.