It is not the piece of paper but the property it represents. If it is a Wallet with just as much as 1 Bitcoin on it, I would should you if you were trying to take it from me illegaly - also considering the fact that you are probably in my house without my consent, which one might argue doesn't even require me to have that piece of paper in my house.

If someone is looking for that particular piece of paper, they probably want it for reasons that distinguish it from the average piece of paper. Also, most defensive gun uses end without shots being fired, so "usually" nobody even has a bullet fired at them.