Those that are more interested in photography, I feel are those that know that every scene changes. When you are working in a controlled environment, I am sure that those u1,u2 settings are helpful to you. However for the majority that is going to be using the camera where the environment and lighting is constantly changing would have a better grasp in adjusting settings to match the situation.
While not everyone will be shooting in manual and adjust ISO, shutter speed and aperture at all times, others may simply use aperture priority, or shutter priority to do what they need it to do. These are the ones that know that the reason why they stepped into using a DSLR for photography is for the adjustability of settings and not to be held back by something other than a point and shoot camera.