Sweat from someone else's arse on the seat is just as revolting as nutt butter.My biggest concern would be hygiene. Particularly with guys. We all know their aim is not perfect on good days. And that's with a "controllable stream".
Imagine the uncontrolled variety. Add that most porcelain is white. And white fluids on white are not particularly easy to spot. I don't want to be sitting down to take a dump and slide my butt against some w@nkers nutt butter thanks.
I always have wet baby wipes handy at work and in my car.