Interesting article. But I think the pet store was likely more to blame, keeping the rat in that condition, than the "back-yard-breeders". I would assume no one even knows if it was a back-yard-breeder. It was probably a rat-mill.
Back-yard-breeders are notorious for not doing health checks or giving their animals to the best homes, but I don't think they are as cruel as mills.
Anyway since you wrote this - I think it'd be a good idea to clarify if it actually was a back-yard-breeder. Usually smaller scale breeders have more to lose by selling animals in bad condition.
But other than that, looks good, shocking story though.