Well I used to have to pay $4.99 a rat at the local pet store that bred them. That's any size rat, even a pinkie! So when I started breeding my own I'd peek in and see a new litter of say 10 pinkies and do a little dance and chant..."I just saved 50 bucks!" LOL

Granted you have to take into account your time and supplies and sort of like with the snakes, if you don't like rats...you're not going to enjoy breeding them even for feeders.