Well, that's all by intention. GIMP and Inkscape have always avoided trying to find that sort of funding: inkscape even allowing their lead developer to be hired away without making a fight for it at one point. It's why I have been trying to copy blender's model for Krita since forever.
What is Blender's funding model? I recall that its initial open source release was essentially crowdfunded before that was a trendy thing, but I haven't been keeping up with how they've been funding continuing development. They seem to be doing pretty well at that, so I'm curious about where the majority of revenue is coming from.
