I would just worry that the best guys aren't going to compete because solely rewarding the first place makes it too costly to play the game
esp. when predicated on the weird whims of the mob.  Now, this is all to say that the way they've set it up is still better than having a panel of art 'experts' decide where you end up with something truly ugly.

But, I dunno... quite a few masterpieces were never appreciated in their time. The truly timeless items sometimes take a few decades to bloom.  I don't care much for impressionists, but it's a good example: van gogh sold one painting his entire life, I think to his brother if I recall. The empirically proven model of producing great art is for a reasonably well educated man of extreme wealth hires specific talent and gives them a specific moment, story or tale to memorialize, my very amateur mind seems to say that that seems to work the best, though I wonder how the people will vote: will they choose dogs playing poker or the madonna and child or a crucifix in urine like Robert Mapplethorpe.  I'd suspect that the various interests in the city will lobby hard for their respective art, so it'll become a contest of who has the best lists and can do the best turnout.  Maybe it'll end up being a mammoth monument to Obama.

Though likely it'll be tony the tiger saying "Grand Rapids is Greaaaaaaaaaat!"