Ansel never saw the money as it was re-sold by the owner. Or try Boulder City in Nevada, or your local art shows in the mall or those aligned with various groups. Look at the pricing for photography. Remember that on this one there are many excellent, creative photographers who are also exquisite craftsmen who can't make a living selling their images. A Photograph is worth what a Photographer charges for it.
Usage has to be factored into the equation as well.
Talent, in many cases, has nothing to do with the worth of the image to many end users. Talents is part of it, but we all know talented photographers who can hardly make a living. Marketing is a major part of the worth of an image while a photographer is alive and probably even more important after they have passed on. State travel bureaus are big in this respect. Really top quality images aren't on the priority list for many of them.