If you guys know a guy that sells wholesale, why not ask him to buy yours? He's obviously getting paid for the snakes, you can just get half or even less, the snakes are gone, no work for you, and you get that little bit of money to put back into feeders.
I have thought about getting something that would eat any hatchlings that didn't make it, just because it seems like there's no easy and humane way of putting a snake down. It seems like expensive trip to the vet or smashing their head with a hammer (I'm not even close to killing rats with my hands, let alone smashing something's head). Freezing and co2 is just torture for them so I wouldn't do that either. Having them fed off naturally just seems like the most humane thing to do.