By making headlines, even on geek news sites, he gets his name out and makes that many more people more aware of his presence on the book stand.
This guy's books are free on his website, not commercially available on book stands. I don't see what he could gain, exactly, other than people seeing his side of the story.
Also, the teamwork aspect is something that you just can't have with computer AI. I can't foresee any computer AI responding to voice chat, like "Can anyone buy me a weapon? Please?".
Actually, in Unreal Tournament 2004(maybe 2003 as well?) if you had a mic and voice recognition set up on your computer you could command teammate bots to give you their guns, hold a point, attack/defend/freelance, among other things.
"The Avis WIZARD decides if you get to drive a car. Your head won't touch the pillow of a Sheraton unless their computer says it's okay." -- Arthur Miller