Because for every breeder like you there's a hundred others who are Doing It Wrong. People think they can make money from breeding their family pet, no health testing, no concern for improving the breed or the breed's welfare, no concept of basic dog training, correct diet and socialisation, no awareness of the fact that so many dogs wind up unwanted and thus dead, just £££ signs in their eyes.
I worry that a lot of people are suckered in by it, people are starting to become more aware of what to look for when buying a pup and most can now probably recognise a puppy farmer but are still so easily caught out by well worded adverts and backyard breeders who talk the talk but actually couldn't give a fig about the long term outcomes.
I will admit to having issues with certain breeds full stop, breeding to an arbitrary standard based wholly on appearance has led to a proliferation of freakish looking animals, add to it the vast majority who are either ignorant of or can't be bothered with the fuss and expense of health testing before they breed and the subsequent rate of genetic disease in dogs is unsurprising and very disturbing.
I think the whole backyard breeder epidemic, the rise of the 'designer crossbreed', the DDA etc. is indicative of a larger crisis affecting dogs in the UK; evangelising slightly here but In Defence of Dogs is a good read if you're so inclined.
I have a bitch here who I could have made a small fortune from, excepting any emergency costs for a caesarean or similar - an increasingly popular and very attractive breed, desired colour, right temperament, excellent hips, eyes clear, great lines, competition wins, bred in the home. £800 a pup would not be impossible. But you know what, there's 20 more the same as her in the breed rescue right now and this time next month there'll be 20 more. I would not be able to sleep at night for wondering if her pups were in a council pound, counting down the days until they are put to sleep. I spayed her before her first season.