I learned that in Pulp Fiction, the gun that killed Vince wasnt Vince's gun, it was Marcellus'. Notice when Butch hit Marcellus with his car on the street, Marcellus was carrying two cups of coffee. See, Jules had given up the lifestyle at this point. Ergo, Vince wasnt suprised to hear noise (Butch) when he came in the house...he thought it was Marcellus.

I did not know this until today.