I believe we now are way out of topic... but anyway!
Neither RHEL nor Fedora (Red Hat does not control CentOS) entirely reject
proprietary software. In particular, both use kernels with blobs. This is a
pity and probably explains rms' disappointment (although it is only a guess:
I have never heard him talk about Red Hat). That said, I believe it is safe
to write that 99% of Red Hat's income directly relates to free software.
Indeed, their business is centered around servers and the usual non-freeness
that creeps into free GNU/Linux systems is composed of desktop applications
(Adobe Flash, Skype, Google Earth, Matlab, etc.) and/or blobs to drive Wifi
or video cards (and servers use neither of them).
By writing that Red Hat "became the first profitable business supporting
Linux", I assume you actually mean "GNU/Linux", i.e., the whole OS. You are
wrong: before it, Cygnus Solutions, which was founded in 1989, was supporting
the GNU (and then GNU/Linux) operating system and was profitable. It ceased
to exist in 2000 when it was acquired by... Red Hat. Michael Tiemann, who
co-founded Cygnus Solutions, now is Red Hat's vice president.
As for Canonical here is what Mark Shuttleworth was saying back in 2009:
All told, Canonical’s annual revenue is creeping toward $30 million, Mr.
Shuttleworth said. That figure won’t worry Microsoft. But Mr. Shuttleworth
contends that $30 million a year is self-sustaining revenue, just what he
needs to finance regular Ubuntu updates.
I believe Canonical taking Red Hat's customer is not good news: Canonical
looks far less committed to free software than Red Hat. On the other hand,
Ubuntu's free packages obviously are a nice base to build Trisquel. :-p
