Well, think about it. He thinks it's gonna be a typical night delivering pizza and he gets to this one house and BAM! Naked coeds! After the initial shock wears off (where he blubbers like a retard because he can't focus on making proper change when all he sees is boobies), he goes about his business, only to realize his job has nothing more to offer him. There might be a naked chick at some point, but it's a once-in-a-lifetime chance and he only has lazy housewives, drunken fratboys, and the other random people at home who should not be seen naked.
And after he realizes there's nothing left in life, he kills himself. His family is stunned until they find this picture. The next thing you know, going naked in your own home means you're a terrorist and those laws about women having to wear at least 3 yards of clothing will be strictly enforced. Then internet pornography is outlawed and we're back to the Puritan days.
All because some drunk hot girls decided it would be hilarious to answer the door naked.