There is definitely cases where realistic images are best. A good example is training and simulation. My favorite example is surgical simulation. Here is an example of a real-time haptic and visual simulation of bone dissection built by Agus and colleagues. At the top is the actual view during a real surgery; at the bottom is the view through their simulator.
The goal of a training system is to model accurately what might happen, so that the surgeon can practice and improve before performing the actual operation. There is clearly more work to do in this area to improve the fidelity of such training devices.
Realism has its role in movie special effects because it allows us to seamless merge the real and the virtual.
Sometimes a realistic image is the best type of image,
but usually it?s not.