This woman and her Bischon rescue have been able to buy so many of the Bichons at puppy mill auctions that the commercial kennels of Missouri (huge ones) are down to a few hundred of that breed! That still sounds like a lot but really for these operations it is not...Read the thing on her rescue page...
http://www.smallpawsrescue.org/pup3/reason.htm
Now I know that some would say that buying at these auctions just lines their pockets, but to save them like that and the numerous dogs that they produce that become breeding stock, well I think is different than purchasing animals at a pet store. You are cutting off the supply if you will! I would donate to that!