I'm guessing these pig tails were sold at a discount. If so, it is probably because this is a genetic deformity. Most reptiles with genetic deformities are generally euthanized by thier breeders. But, if they can find someone who is willing to buy and live with a deformed turtle, more power to them. Some turtle breeders get get big bucks for their deformities: two headed turtles, turtles with no eyes, ect.