That's a fair point....
Playing devils advocate, I'd suggest that the breeders you mention are motivated by more than money, and have the means to deal with situations like the one being speculated upon.
Would they have taken a litter with Parvo to a vet? Doubtful. An experienced breeder would probably recognise the symptoms, knock the pups on the head, and get the disinfectant out hoping that word didn't get around they had Parvo.
As I say, just playing devils advocate....
by their own stupidity they've messed up their we earner, who's going to buy pups of them any more, he