Upon first taking someone to this
Mecca of baseball, you must tell that person about "A guy I know that..."
In the Wrigley Field men's bathroom they have trough style urinals unfortunately they also have trough style sinks, telling the too apart can be difficult for a newbie.
Usually the story goes... Foo pees, as he zips he gets a funny look from another guy, Bar, who didn't see him pee and wonders why Foo is adjusting his fly at the sink. Foo starts looking around for a sink. Meanwhile Bar, of course, comes up and washes his hand where Foo just relieved himself. Foo runs like hell out of the restroom, while Bar reminds himself not to let Foo serve him food.