Even painters discuss the phenomenon with regard to different other mediums: Why does an oil painting fetch more money than a watercolor, and that more money than a pencil sketch?
It goes even deeper than that into the subject matter of what you draw, let alone the medium, landscape painting is considered the lowest form of art, followed by still life, portraiture, composition and gallery composition at the top. The latter is especially hard, because how many artists can turn out masterpieces consisting of complex subject matter, on a regular and consistent basis? Maybe a couple in this day and age.
In comparison, photography generally requires the same amount of time and energy investment regardless of the subject matter: Landscape photographers need to travel, but don't need extravagant equipment besides a good camera and lens; studio photographers don't need to travel, but need a good studio space with equipment; sports photographers need expensive gear and the rights to shoot from the front row, and so on. It always requires an investment of some kind, just different kinds to suit different people, but rarely is one kind of photography dramatically more taxing than another; except maybe wedding photography, though the payoff is also so much greater to make it potentially worth it to some.
Oh, and the art world is not afraid of photography, in fact, without it a lot of artists would be in quite a fix you see... I shoot art reproductions professionally, which means I essentially create a perfect digital copy of an artist's work that they can use for everything including magazines and catalogs, to creating full-on copies of the art work. It would quite daunting for any artist, even a master, to actually paint their pieces from scratch if someone wanted a copy.