To be honest, I think saying that being a billionaire is unethical is farfetched. If someone made that much money running a business ethically (assuming that's what Feeney did), then I don't see why anyone should feel guilty for becoming wealthy. And the guy is old, in his 80s now I think, so he knows that there is no point hoarding all the wealth he accumulated if he knows that his time will come soon.
To be honest, I think saying that being a billionaire is unethical is farfetched. If someone made that much money running a business ethically (assuming that's what Feeney did), then I don't see why anyone should feel guilty for becoming wealthy. And the guy is old, in his 80s now I think, so he knows that there is no point hoarding all the wealth he accumulated if he knows that his time will come soon.