When there is only one open urenal next to two guys. You walk up and get ready to go, but then you notice they're looking at you out of the corner of their eyes. To prevent from being checked out, you waddle all the way up to the urenal, effectively hiding your privates.
Guy, "Aw man, one open urenal. I guess I'm in for a game of hide-and-go-pee."
Guy1, "I got to go, but theres only one urenal left"
Guy2, "Just hide-and-go-pee"