Are NGOs exceptions?

I was listening to this interview by Matt Brandon (@digitaltrekker) with Trey Ratcliff today and after leaving a comment on his blog I decided that I will write a post about it here as well. Towards the end of the interview Trey is explaining his reasons for posting images on-line under Creative Commons license BY-NC-SA, one of them meaning no commercial uses. And the question was asked – what if an non-profit organization asks to use images. And Trey explained, that they would have to pay. Those organization would not only use those images to bring in revenue, but they also have budget to cover costs of running business, such as employees are being paid their salary, thus it is only logical that they pay to use images. And this are in fact great arguments, and I totally agree with them. But.
Just take a look at this blog post to see how important it is for NGOs to have in hands good quality images, which they may not necessarily be able to afford. I wonder then, if those organizations, for what their mission is, shouldn’t be treated differently from other commercial entities. If the images for them could/should be treated as charity donations or received at a discount price because of limited budget and importance of what they do.