The world is a community. Not just a bunch of wealthy people.
Did you read the part about when a dog has enough he shares? Did you understand that? When there are folks starving and when there are folks with way, way more than they can ever use for their own selves, it's time to share.
At gunpoint, if they are so attached to their stuff they don't mind others suffering, others dying, others starving. There's something wrong with people who hoard more than they'll ever, ever need, don't you think? Especially when that hoarding causes suffering in others? You don't want people to suffer, do you?
Who'll determine what anyone needs? Me. That's a great answer.