I agree but the public policy reason of deducting such amounts from the estate is that these organizations provide goods and services which benefit all people and also supplement or provide what the government/public would otherwise have to provide. So, yes we are still borrowing from our future wealth when we take from the wealthy.
Where did you come up with that one? The real reason is that the very wealthy have effectively lobbied Congress to pass laws so that they can shelter their wealth for their progeny. These charitable or other type Foundations use their wealth to employ the survivors as directors and to use their influence around the globe. Gates and Buffet will use lots of their Foundation money overseas. Americans won't benefit from it.