Obviously, much of the reason many people (the non-professional public) like 16:9 so much more than 4:3, is that they have been programmed by public theaters to expect 16:9 as being of the highest quality, as if 4:3 television programs are of a lower quality. While professionals realize this is untrue, we must try to appeal to the largest audience to be as fiscally successful as possible. This is similar to the way everybody goes nuts for 24P, when in fact 30P is probably a better format/frame rate.
However, one actual advantage 16:9 has over 4:3, is that it more realistically recreates the aspect ratio of human vision.
The funny thing about that is when people discuss the "real" look of 60i, vs. the "narrative" or "fantasy" look of 24P. Now we should say that the "real" look would be 60i, 16:9, and the "fantasy" look would be 24P, 4:3!