As "Farenheit 9/11" proved, and as Hollywood itself knows, there are $100 million grosses available in making movies that the right never goes to see.
If politics don't enter in, and nobody boycotts your movie, you can make $300 million with "neutral" movies, but Clooney can live in his Italian mansion on what he makes from his fans alone.
Since most all of Hollywood is pretty much left, it really ends up being a matter of personal presentation that makes actors "accessible" to the public, or not.
Sean Penn has always seemed unbearable off the screen --he criticizes other people's movies as being "trash rather than art" and then makes movies like "The Crossing Guard" and "The Pledge" which have their own flaws AS art. He publically critized his "friend," Nicholas Cage as "an actor who became a performer" -- and then makes "The Interpreter." He acts like the "tough guy from the mean streets,"but he grew up rich and privileged on the beach in Malibu, the son of a very successful TV director of shows like "Columbo" -- and with immediate access to the casting agents and inside dope of Hollywood.
Clooney is more charming than Penn, but he acts sometimes like the Big Man on Campus who gets a kick out of making fun of everyone else.
Clooney had the entry level skills for TV or movies--handsome, great voice -- from a young age. His aunt was Rosemary Clooney, her ex- was Oscar winner Jose Ferrer, Clooney's father in law from his sole marriage was Oscar winner Martin Balsam. Those talented oldsters may have been has-beens and struggling at the time that George Clooney was starting out, but surely they gave George pretty immediate entree to the Hollywood hiring structure when he moved out to LA from Kentucky as a young actor.
And then Clooney took off. TV shows (Roseanne, ER.) A divorce from Balsam's daughter Talia and an endless run of beautiful girlfriends. Movies. Wealth. More handsome all the time. A pretty easy ascent.
Which is just my way of saying, Clooney's smug and confrontational stance sometimes seems off-putting, as if he doesn't much understand how easy it was for him, and as if he enjoys putting down others who'll never have his life of babes and wealth. So evidently some folks are choosing not to help out with that life.
Cary Grant is offered as Clooney's model, but Grant was a pretty reclusive and mysterious fellow. Clooney's heart is on his sleeve, for better and a little for worse.