The way in which owning a physical thing "makes sense" is that you can defend a physical thing. You can move it to a location that's easier to defend, or build defenses around it, or whatever. Physical property is about defensibility; it's not a metaphor, but a capability. Information-as-property is a metaphor, precisely because defending the part you "own" of (what is otherwise) someone else's computer is so difficult as to be effectively impossible.