Martin (who happens to be the author of the blog, not the actual George RR Martin) responded that:
It plays into the artificial and embarrassing Us versus Them divide that is sadly all too common within the genre community. Beyond the stupidity of jamming his thumb on the scales and simply assigning high status words to the thing Martin likes, however, is the amusing contradiction that those high status words have to come from reality. As Sam says, you certainly couldn't get a bloody steak in reality, could you? At the most basic level, if Martin can't write movingly or beautifully about the strip malls of Burbank (and I'm certainly prepared to believe he can't) then he has no business writing anything. He is basically saying he has no eye, no ear, no empathy. And that is why it is speaks to the problem of commercial fantasy in general.
To which I replied: