Well, because of a severe lack of room in my house(I don't have a garage and you couldn't get a cat in my attic let alone swing it) once my bushcraft/survival kit is squared away it all goes in the back of my car(except my sharps which are locked away in a safe place to prevent my son getting his hands on them!), so I guess if I did break down on a dark cold winters night in the middle of nowhere(Which isn't really likely but as one of you has already stated "It could happen") I think I would be alright.
I also keep the other usual stuff aswell - oil, water, FAK, Break down kit, a nice size warning triangle, Flashing light etc..