Well, I would say that "fancy" popular breeds cost more than good hunting dog breeds. But pedigree is more important than breed. But with the case of hunting dogs it's not the dog show champions that counts, but the hunting champions. A hunting dog that doesn't get excercise normally just becomes a bad hunter, while for example sheperd dogs like a border collie would go crazy. And a watchdog I wouldn't even think of having as a family dog. Also remember that all dog breeds, except Papillon AFAIK, are originally working dogs. The Poodle for example is a water fetching breed, which supposedly explains the classic hairdo. It's supposed to keep its joints warm. And the Chihuahua is originally a watchdog, not the dangerous kind, but the kind that wakes the Bloodhounds.
Light moves faster than sound. That is why some people appear bright, until you hear them speak. List of common misconceptions