A monetary loss is likely to be more damaging to a person with little money, but the theft of something with mainly sentimental value would likely hit each person equally hard.
I mean if you steal from the rich guy and he can't buy his diabetes medicine that day, and so ends up loosing a foot, I'd say that'd be worse than stealing a poor mans money and having him go hungry for a day. Just to pick an extreme example.
My point is that a theft becomes morally worse because of the consequences it has for the one it's stolen from.
Simply put: The more damage the theft causes the victim, the worse the theft was. It doesn't really matter if the victim is wealthy or poor.
I mean if you steal from the rich guy and he can't buy his diabetes medicine that day, and so ends up loosing a foot, I'd say that'd be worse than stealing a poor mans money and having him go hungry for a day. Just to pick an extreme example.
My point is that a theft becomes morally worse because of the consequences it has for the one it's stolen from.
Simply put: The more damage the theft causes the victim, the worse the theft was. It doesn't really matter if the victim is wealthy or poor.