Felinik: Aside from the possible Marketing explanation I proposed earlier, I don't think you're going to get any real answers. In the end all these types of discussions collapse into an inevitable singularity regarding the essence of what makes good or bad or popular photography (or art in general). Grain, seeing through grain, leading a viewer's eye, "communication", composition etc. are all red herrings in my opinion. Either you dig it or you don't. And any reason is valid. That's all there is to it.
One man's perfectly composed, perfectly timed, perfectly exposed, perfectly printed, perfectly communicative masterpiece is another man's piece-o-crap. And the same goes for an out of focus, grainy, underexposed, stained, badly "composed", polytoned, lith whatever.