My laptop has an AMD graphics card but unfortunately it doesn't work with Linux. It's really good to see more and more support, though, and I think that we'll see even more thanks to Steam working to make more games compatible with Linux.
And it's absolutely true you can make money off the back of a free product through support. Perhaps you can even make more money. But unfortunately, Windows has become the "standard" and people are scared of change, which is a shame.