Brit, I'm a big fan of the SPCA but I think they're talking rubbish here.

Dog breeders that breed dogs with the intent of showing them are extremely aware of what inbreeding does to the breed. Normally they only inbreed for show purposes when two dogs are really really good. Dog breeders that show dogs are very different to breeders that do puppy farming.

The kennel club have standards for each of the breeds. If a dog falls outside those standards by being deformed, they certainly do get disqualified from the show.

Most dog breeders that I know (and I know quite a few of them in Brazil) breed for the passion of improving the breed and would never do anything to jeopardize the dogs.
In fact, I know some breeders who won't even sell small dogs to households that have children under a certain age.

There are several types of shows. The SPCA only mentioned one type. This type the dog MUST comply with the standards, of course, otherwise why bother. It'd be the same as saying that human beings taking part of beauty pageants should not be judged according to how beautiful they are. Bollocks! Same with dogs. But make no mistake, a dog's personality is part of what is judged, i.e. if a dog has terrible personality the judge will not overlook that. In fact, if a dog bites the judge it will be immediately disqualified.

There are other types of shows that the beauty is not taken in to account: obedience trials, Canine Good Citizen tests, field trials, agility trials, lure coursing, rally, hunting tests, herding trials, tracking tests, coonhound and earthdog events.