First of all, it wans't a box of onions...

Snopes sniffs a little too close I am not sure that the estimable Snopes site will ever be challenged to debunk a gospel truth story that a certain roommate of mine once told.
I am inclined to say that this garbage tale, and the cat-in-a-bag that it links to, are both tame parables compared to his legendary "come-uppance for stealing" story about a box of onions in the attic.
I believe that the story is true and woe to you that tries to challenge the teller. When crossed he's been known to perpatrate vile deeds upon your car's ventilation system.