When we adopted Zack in 2001, he was in a kill-shelter and his days were numbered. He had been previously adopted and returned to the shelter for unknown reasons. We also rescued Buddy from a local shelter.
Twenty-five percent of all pets brought into animal control or county-run animal shelters are purebred dogs. This means that someone bought a pet from a breeder or pet shop for hundreds, sometimes thousands of dollars, and a few months or years later, surrendered the dog to a shelter or abandoned the pet to fend for itself.
Since the Labrador Retriever is the #1 dog in the U.S., according to the AKC, Labs and Lab mixes are also the #1 dog in animal shelters and/or humane societies. Many owners do not realize that Labs do not fully mature until approximately 2-3 years of age. They also do not seem to realize that these dogs need direction & training to compensate for their high energy level. The #1 reason that Labs are in shelters is LACK OF OWNER COMMITMENT. Some people find it easier to dispose of their pets than to take the time to train and exercise them.
Whether you are looking for a purebred or mixed breed dog (or sweet cat), please consider looking at your local shelter first. A good place to start your search is http://www.petfinder.com/.