Sure, if you're only weighing the cash prize. Contests like this often involve competitors spending more than the prize, certainly in total among all entrants, but sometimes even by the single winner.

But it's clear there are many other motivations at play: the excitement of the competition, the chance to learn based on a real-world problem and dataset, the fame available even to those who reach goals other than final victory. And many of the results can be published as papers or open-source software, as well.