We were taught that sort of thing as part of health education.
Two college guys in a bathroom:
One finishes peeing, starts out. Other guy says, "Hmmmph, at Princeton, we were taught to wash our hands after peeing."
"At Hahvahd, we were taught not to get pee on our hands".
...and the Princeton guy replies, "At Princeton we know the pee is sterile-- it's the "equipment" that's covered in e. coli bacteria, you Haaahvahd dumbass."