I only can assume that OP is type of the guy who dislikes washing his hands after doing his business in a restroom. I seen so many douches of that kind in college restrooms to the point where i stop using public restrooms unless I really really have to.
I remember reading some 4chan story about a dude that did first time anal with his GF and ended up discovering some worm business going on in there. I will never be able to unimagine.