Buying an adorable puppy or kitten at your local pet store may become a thing of the past, if more American cities join a small but growing movement to ban retail pet sales. West Hollywood, Calif., became the latest city to put a leash on pet sales in February, when its city council unanimously approved an ordinance prohibiting sales of dogs and cats in retail stores. Albuquerque, N.M., and South Lake Tahoe, Calif., have also banned pet sales. Other cities in Florida, New Mexico, Missouri and elsewhere are considering similar bans on the sale of dogs and cats. Animal advocates say pet store sales fuel the puppy mill industry, where dogs are bred and raised in cramped, unhealthy and inhumane conditions. They have similar concerns about "kitten factories," which are a smaller but growing problem. Efforts to crack down on animal mills have been hindered by limited enforcement resources, so ban proponents are shifting their focus from the supply side to the demand. Far better, th