I think people notice the 'Robotic' running on PES much more than on FIFA..
Play a game on FIFA and concentrate on how the players run.. They run like robots too.
People notice it more on PES because all the concentration is on one player. On FIFA it is more of the whole team I concentrate on, but on PES if a player on the wing gets the ball I seem to be watching his every movement.
Whether its because the camera is closer, or maybe because the players seems a little chubbier on PES, the robotic running does stand out more on PES.
Don't get me wrong.... FIFA does have better running animations, but it is just way more obvious on when I play PES.
I don't know why, but it just does....