You are operating on a massive assumption that the public good is best served by government spending via taxation. The Gates foundation, by any measure, has way more bang-for-buck than equivalent public programs. Viewing wealth as antithetical to charity is a depressing view since the government you love so much has several orders of magnitude more wealth than Gates yet floundered with similar projects. I would much rather polio be eradicated by Gates foundation than wasting that money in a federal pit.