Commercial support for free software makes plenty of business sense.
Check out Free Grows Revenue – Just Ask Your Carrier. =)

Excerpt:

Because no Fortune 2000 customer on earth is going to run the heart of
their enterprise with products that don't have someone's home number
on the other end. And no developer or developing nation, presented
with an equivalent or better free and open source product, is going to
opt for a proprietary alternative.