From my point of view they do know how to make money.
I recently upgrade from 5 to 8, mainly because I needed to work with others that had version 8 and naturally version 5 can't open those newer files anymore. What I got with upgrade was lot better texture mapping tools, I could open new files and I needed to install more ram to my computer, 1GB seem to be absolutely minimum to work with 8.
So it has not been huge changes in every new version, but just enough to get companies that use software in their business buy always next version. If Blender would be just less learning I would jump to it, but things are done so differently in Blender that it is really impossible to even consider changing now.