Owning a dog costs money though, food and vet bills etc so they would be better off without the dog in the first place. If the bitch was to struggle during giving birth they wouldn't have the funds to pay a vet to sort it out, how's that fair on the dog?
Exactly owning a dog is not cheap a few years ago my wife and i went to the rsp a and tried to rehome a dog, the lady behind the desk asked what we do my wife was at uni at the time. The reply was so are you going to get a job then to which my wife replied well yes of course she then said well who will look after the dog then.