Left hand or right hand who cares?

Well, like almost everyone I guess, I like watching movies on my free time. And if it's an action/thriller movie, my wife often likes to watch too. So far I never caught anyone writing with the right hand in a movie… whenever there is writing going on in the scene, people are always using the left hand. Of course it's nothing unusual for actors to be left-handed, just that it would be a strange coincidence if they all were in those scenes, since there are far more right-handed people in the world. Could it be that people who use their left hand are more creative thinkers while those using the right are more analytical?