[mjn]

Meh, any piece of art in this price range is typically being bought mainly for the right to own "the original" of a piece that had some kind of historically important role. Sure, you can copy lots of things, which is true of older art, too. For rather less than the price of a Picasso you can get a very nice, extremely accurate copy that requires forensic methods to distinguish from the original (though some artists are easier to duplicate precisely than others). But it'd be a copy, and some people are willing to pay millions to "own a piece of history". There's no real reason that'd be different just because the piece of history is 20th-century art history, and/or you don't like the piece or the artistic movement it was part of.

Heck, one of the points of Warhol's art was mass-producing screen prints, and people still pay a lot for an original, rather than a screenprinted reproduction.