For existing projects with an established user base, the changes necessary for Gridcoin are small and usually already in place. That is why some originally didn't know about being on the whitelist.
In terms of encouraging new projects, setting up a new project is a significant investment of time and resources. There is nothing free about the computational power. I would know since I have tried to start a BOINC project before, for my research, and failed.
This is a really good point. I agree that we should incentivize new projects to join us. I'm not sure that the solution is by giving more GRC to crunchers who crunch those new projects, though.