The point of Hollywood Stars though is to recognize classic stars. AKA those who have been around for a long time.
If we were to compare it to actors, who do you think would be more deserving of a star? Someone established, like Tom Hanks, who's made tons of great movies; or some relative newbie, like Tom Welling, who's only contribution so far has been playing Clark Kent on Smallville, and a bit role in Cheaper By the Dozens? This is not to say that Welling is not a good actor (I think he's pretty good), but he's just not as established as Tom Hanks.
So Mario in the video game world = Tom Hanks in the acting world, while most newer video game characters = Tom Welling.
If there's any video game icon more deserving of a star than Mario, it would be Pacman.