Part of the work is determining through what instrument you are playing. Actors are physical, olympian storytellers and we should be able to create entire landscapes with nothing.
Making a film is so hard that if you don't have your main actors going along with the ride with the rest of the crew it can make your life very difficult.
People want to see realism in action now. People want the actors to perform than the computers performing. Though I have done both, I enjoy the realism of action more.