Because he's coming to PAIN as a downloadable character, that's why.
Mr. Hasselhoff will make his debut on "Hoff Day" along with a new movie studio level on Novmeber 6. Oh, they also got him to cover Culture Club's "Do You Really Want To Hurt Me" while they were at it. I... don't think I like PAIN enough to get much of a rise out of the actual content, but I will say that the post on the PlayStation Blog is good at...
A) making me feel sorry for David Hasselhoff
B) making me feel old in the process
A and B happen for the same reason, too. The blog post is peppered with links that are designed to fill you in on who the hell David Hasselhoff is/was. Phrases like "I know you’re probably wondering 'What in the KITT am I doing on the PS Blog?'" are already shake-your-head material, but when they go and link "the KITT" to the IMDB page for Knight Rider because no one remembers what the hell Knight Rider is anymore other than a completely terrible new series about a guy and a car, I want to start telling the kids to get off my lawn.
Speaking of you kids, before Knight Rider was a horrible new show, it was a passable old show.
Also, here is David Hasselhoff learning kung fu for an upcoming movie role. As seen on the DAVID HASSELHOFF SOCIAL NETWORK.