You're assuming all this money finds it's way to benevolent causes that the majority might agree with (environmental sustainability, helping kids etc). Do we have any idea about how much of it ends up funding quackery and personal-agendas?

Of course, it is their money and they can do as as they want with it but if it has a large impact, I can see the argument for more transparency about the source of funds.

Edit: For example, less than a minute of online searching leads me to this kind of example: http://en.wikipedia.org/wiki/Greg_Gianforte#Social_and_Polit...