I agree that we may see a bunch of empty cars, but Disney may try to get Genie (free version) to keep throwing notices to the 1st timers or in-experienced guests that 'Hey, Rat VQ is open for reservation RIGHT NOW no wait' to make them think they won the lottery and pull demand from other VQs.
Based on the above, you'd be crazy to pay for Rat, but you'll have to wait until you use up one of your other free VQ reservations before you pick the Rat VQ.
But yeah, Rat is a fast loader and there is no legit demand reason for it to go VQ