I always, ALWAYS educate about petstores and puppymills, even if the person has recently bought a puppy from a petstore. I just can't help myself. Generally after a person tells me they got their pet from a petstore, I will ask if the new puppy has been healthy
so far. If they say yes, then I go on to tell them about how we weren't so lucky with our pug dog that we purchased from Pet Habitat in Brentwood Mall, BC. Then I explain to them about all the health issues she's had over the years, and how most of them weren't obvious in the first couple of years. The lastest health problem that I tell them about is her worst one. It's called spondylosis (degenerative disease of the spine). Our pug "Tang" was diagnosed with this disease at age 7. Our vet told us that she has this disease from being poorly bred, and it is likely that both her Mom and Dad would have had the disease in order for it to be passed down to her. She is slowly becoming paralyzed and there is nothing that we can do for her other than pain killers/anti-inflammatories, and live with her peeing and pooping everywhere because she has no feeling from the waist down. My dog can hardly walk anymore. She stands with her back sloped and kind of drags/scuffles her feet behind her. I have to carry her around most of the time. To watch her suffer, and KNOW that it's because of how she was bred is truly heartbreaking, and something that I wouldn't wish upon anyone. I can always tell by people reactions that my story does "hit home". I will continue to educate everyone I can when it comes to pet stores and puppymills. I just be sure to do it in a kind, informative manner so that people will listen with an open mind. Someone has to speak up for these furry little ones, so it might as well be me! The only way of stopping puppymills is by not purchasing these puppies. Apparently, not even pressing criminal charges against these pet store owners will stop them, because the owner of the pet store that our pug "Tang" came from is still in business!
Pet Habitat in Burnaby Charged with Animal Cruelty
BCSPCA Press Release May 4, 2005. For immediate release. Crown Counsel has approved charges of animal cruelty against Thomas Peters, owner of the Pet Habitat store in Brentwood Mall in Burnaby. BC SPCA animal protection officers have responded to nearly 80 complaints from the public about the Burnaby pet store during the past five years. "The primary concerns have been lack of proper veterinary care for sick or injured animals and filthy or substandard housing conditions," says BC SPCA Senior Animal Protection Officer Eileen Drever. "We have responded to frequent complaints at the store and after each visit the situation improves for a brief time but the animals are soon subjected again to the same conditions." Recently, SPCA animal cruelty officers discovered a Fox Terrier puppy at the store in thin body condition with its ribs visible, lethargic and depressed, with laboured breathing. An order was issued to seek immediate veterinary care. At that time birds were also observed with overgrown twisted nails, and cages were dirty and overcrowded. Smaller animals in the store were also inadequately housed. "During another recent inspection of the store SPCA officers found a bird with a broken leg," says Drever. "Unfortunately, the Fox Terrier puppy and the injured bird were subsequently euthanized." The SPCA forwarded a recommendation to Crown Counsel that Mr. Peters be charged with animal cruelty with regard to these recent incidents.
If that's not enough to make someone never purchase from a petstore again, then I don't know what is

I won't even buy pet supplies from a store that sells animals.
I guess that was a long-winded answer to your question, but I guess my point is that I feel it's important to say SOMETHING at least. If they've bought one puppy from a petstore, chances are they may buy another in the future. Especially if their most recent experience wasn't a bad one.