Pet quality means that the dog doesn't adhere as closely to the standard as would prove successful in the conformation ring. Pet quality for working dogs could also mean that the breeders don't believe that the dog has enough drive to succeed in trialing.
You're going to get pet quality dogs in nearly every litter no matter the pedigree of the dog. Every dog in the 5 generation pedigrees for the dam and sire of my Cocker is in red, but half the pups in the litter were still deemed "pet quality". Sometimes it all comes down to the minutest detail when it comes to selecting which pups go to pet or show homes. Sometimes even very experienced breeders can't fully predict how a dog will turn out and a pup sold as a show prospect won't turn out as well as a sibling that was sold as pet quality.
If a breeder isn't breeding with the intention of producing conformationally correct dogs usually you're not going to end up with pups that adhere closely to the standard. However, that doesn't mean that you shouldn't give it a try and see how your dog does. As others have stated, this could be a good opportunity to learn, network, and ease your way in the world of showing.