Why DO outhouses classically have crescent moons on their doors or their sides? Is is an ancient hold-over from when boys outhouses had suns on them and girls had moons? Is it a decorative way of bringing in ventilation and light? Is it an allusion to "mooning?" A cut-out to act as a handle for opening the door?
Hah. The answer is far less interesting than any of that. But hey, did you hear about the time that a fart ended up getting 10,000 people killed?