And if the janitor was, they deserve to be fired. If everyone is doing it, like you are hinting at, it should not be a fireable offence but really most places you work you would get fired over it. Meaning, I am not the only person offended by this, and its not what is considered normal behavior, at least according to most bosses.But just think of what happens to your work space when you're not there.
The janitor could be having relations with his girlfriend...or her girlfriend...or his boyfriend...right where you sit.
(Do they sell Luminol to the general public?)