You're a little late with this article, aren't you?
When I tried out Ubuntu back in 2008 it had some proprietary software and stuff you could buy as well as all the free stuff. For many years it's been possible to buy some proprietary software to run on Linux, like Cedega and Crossover, it's just Ubuntu made it available through their main repository control centre. Which made it easier to find and install, and also gives you a better feeling that it'll work properly or they wouldn't have it there.