At work here, we share our washrooms with the office next door. The people over there are pretty nasty though. I don't know where the heck they learned how to use the washroom, but we would find some of the nastiest stuff in there. They'd pee on the floor, pee on the toilet seats, get the rolls of TP soaking wet and other nasty stuff.
This morning, I went in and found a small piece of turd on the floor. I got out of that stall right away, but while turning around to leave I noticed the TP holder (it's a metal box) had streaks of brown on top of it. I don't know what the heck this one guy was doing in there... playing with his own doodies?
Anyway, I hate using public toilets, and this kind of stuff is the reason.