Charity is about who benefits, not about who decides how to provide that benefit.

The idea of choosing a charity based on the donor’s will of how it will get spent describes almost all types of charity. If someone donates to any charity at all, they have made a choice on how to allocate their resources and they just take it on faith that that’s the people who need it the most.

Furthermore, any given dollar of his can only be spent once. The money he spent on himself enriches himself. It’s a considerable amount of money but it’s a tiny fraction of the money he controls. Any dollar he gives away can’t be spent to enrich himself.

Finally, Buffet has donated over $57 billion. How is he supposed to distribute that? Fly a plane around the country and dump cash out the window? Send a huge check to the IRS? Give it all to your favorite charity? The obvious answer is that he sets up an organization that will analyze existing charities for need and effectiveness and then distributes his assets accordingly.

That would be true if he were secretly using those charities to enrich himself but there’s no evidence of that at all.