Don't mind Angel, his comment was silly to the extreme. According to such a view, art contests are somehow a moral crime.
Are you an artist by trade? If not, then screw off.
And if you do something else would you be willing to perform your job for a week or more with only a slim chance of getting paid for it?
Professional companies should be hiring an artist to do the work. Not soliciting thousands of unpaid man-hours from the player-base.
And in this case they're not even spending their own ****ing money. They got a bunch of donations, then they asked for a bunch of free work so they can pick and choose the best and give the guy money that they were given to do the game. What a racket.