If you stood me in a costume next to a computer graphic of the same-looking character, I think there would be a difference. And many movie fans I've spoken to would rather see an actor in a costume than CG.
“It's like a novelist writing far out things. If it makes a point and makes sense, then people like to read that. But if it's off in left field and goes over the edge, you lose it. The same with musical talent, I think.”