It’s actually worse than that; it’s not really about the funding, except that the funding is a means to an end. They think they are patriots, that they are “the good guys”, and they’ve convinced themselves that the things they do are necessary to “save America”. The NSA people are the same.
If our spook agencies were merely venal you could buy them off for the benefit of everyone. Unfortunately they have their own strange sense of honor, that allows them to torture and murder people but doesn’t allow them to be bought off.