Celebrity Golf Balls

I wonder why more celebs with a keen interest in golf don’t launch their own balls?
I found this funny vid for the ‘Dino’ Dean Martin golf ball.
Who next? How about the ‘JT’ Justin Timberlake ball, especially now that he works as a design consultant for Callaway.
Then there’s Bill Murray and Cameron Diaz. Who wouldn’t want to play with Cameron Diaz? -------------------------------------------------