Well, when you group all non profits into opportunities for "greed to happen"...then I'm just afraid you're bitter and unnecessarily cynical. Generalization happens. 
Look, perhaps the truth slides along the scale at various points, depending on the actions of those individuals involved.
I believe wholeheartedly in the Shedd's mission, and the Ralph's vision for it. I have personal experience on the value of the service they provide, as both a consumer (concerts) and a provider (classes, lessons).