What a bunch of whining about 'fair'. It's simply the market at work - nobody
owes you anything, not a certain amount of money per hour, not a certain amount of work, nothing. As long as there are people who want to do the work for the payout they get, the system
works. If you find you can't make enough money on 99designs, you're free to get a job at McDonalds.
RFP's don't lead to BIG gains either - there are many contracts with a cost plus model. And most startups fail or whither on for years, with no real prospects. That's just how it works - don't like it? Feel free to do something else.