All but my Goldfish, Pleco, 3 of the 4 females and my butterfly CT (those were from petsmart) are from petco. They get some nice fish in. I know many pro breeders that breed for show say "Don't get fish from pet stores" and I think thats bull. Just because most of them are mutts and not "pure lines". Thats dog show crap. Even when I showed horses I never had the "pure one", but I still kicked everyone's butt!
I think it is possible to start your own line from a pet store fish. It might take a long time to get just the right one to where you can show it, but I can be done! Really when you think about it in the animal world and what we have done to create new and cool looking colors, shapes and so on.....everything is pretty much a mutt in its own way, even us humans!
Sorry for the short rant. Sometimes "standards" make me a little irritated.
Here are some photos of my babies ^_^