At Forbes.com, Judith Dobrzynski tries to explain the widely divergent reactions of the art world and the general public to the Rose story.
She lists a bunch of reasons why the public has come to see art "as a tradeable commodity."
One good reason that doesn't make the list is that (whatever else it may be) art is a tradeable commodity. People trade it every day! (Even museums.)
The Art Market Monitor had some similar thoughts a few days ago here ("What seems to amplify the problem is the very success of art in recent years in market terms. Without a market value, the museum would not be a container of assets the university might view as, well, assets.").