I think it's because the more restrictive license of the Linux kernel (GPL) vs the more permissive BSD License. What Google is doing technically doesn't violate

I think it's because the more restrictive license of the Linux kernel (GPL) vs the more permissive BSD License. What Google is doing technically doesn't violate the GPL but it kinda gets away doing the sort of thing copyleft licenses were intended to prevent. People have been upset at Ubuntu forever too since they started including closed source drivers.