I think there is the whole, art is in the eye of the beholder argument - but - there is also the good old, name = prestige. Chances are all of us here Could take that shot, but, would any of us even think of consider showing it that large? image: --- that's pretty huge! 73 x 143 in ---6 feet by close to 12 feet...huge. Gursky can and did do that because he has both skill and the name and of course the lab and his own giant printer too.
It's sad because I see so many artists making such amazing things...selling them for $100 a pop, then see this---yeah gursky's is huge but...it's 4 million not because of the content ---
Face the facts - it's 4 million because it's a gursky. Same shot printed to same size by unknown fill in the blank artist - well, your talking a few grand at most because - unkonw fill in the blank artist isn't known, has no acclaim. Where did this thing sell, christies, and yeah, they cater to the rich, the rich want bragging rights, they want that piece on the wall that will be the talk of the next cocktail party (mind you, the cost of the cocktail party for this rich guy alone is probably more than the unkown artist would would get for his print) ---ohhh it's a such and such...
Sorry if that ruffles feathers, but it's true...