Interesting take on the matter.
I think that it's extremely likely that most of these philanthropist projects are in fact just ways to go around tax laws in order to minimise taxes, as well as creating a better public image for the person why has built this fund himself.
Notice how he's creating a fund, and has not actually donating anything to anyone yet. I'm not saying that he won't, it's just something to take note of.
And Piggy's completely right - if Bezos does want to become a philanthropist, perhaps he should start with the most manageable and easy to change thing - the working conditions under Amazon themselves. But obviously that would cost the company and himself much more money to do and isn't as "cost effective".