To use any of those weapons, the wife has to open the door.  Much safer and less confrontational to simply not go to the door in the first place.  If it is truly a full-fledge creep, a door slightly ajar and someone arguing or aiming is an invitation to escalate.  Him on the step and the wife inside and firing a gun ends up in a legal mess no one wants to begin if they don't have to.  If it turns out to be a neighbor or other harmless person, they simply think the wife isn't home or is stand-offish, which isn't fatal.