A person who breeds purebreed dogs for the "money" aspect. This is someone who has one or more intact purebreed dogs that sees the prices that pet stores recieve for that breed and says "I could make that kind of money"
While not quite as bad as puppy mills they fill thier own niche. People warned away from pet stores, but not fully informed why (or even fully informed) can fall into the trap that they are getting a puppy from a respectable breeder. But many times the breeder has not done proper health and temperment testing. Just like at a pet store AKC registration is used as a seal of a superior dog.