Stories of a short, fat bastard.

It might be possible under these rules for some unscrupulous individual to re-define themselves as a robot's 'owner' on the way to the shop, because this is a changeable value. If someone re-defined themselves as the robot's 'owner' then it would be incredibly difficult for the original owners to get that robot back. You shouldn't have a changeable value like that, it weakens the rules considerably.