
I am sorry you have read it that way, because that is NOT the sites' intention;
Its overall aim is to try and prevent people buying labradors irresponsibly. It is probably little different in other breeds, but the labs increasing popularity sadly has them seen as 'money spinners' and there are people out there deliberately breeding without health tests and spinning naive puppy buyers massive yarns on everything from health tests to KC registration (and probably lots of people inbetween) - there are also some doing so because they know no better :( (should ignorance be an excuse? - not really - but no-one is perfect).
Like you, I know only too well that even with the best care in the world, there are no guarantees - sometimes there is also no logical or justifable cause.
If you read the health testing section, it does show that there are other causal factors for HD - and the section on ED also shows that environmental factors can play an insignificant role. Some of the stores even clearly state that they do not know if they MAY have unwittingly played a role in the condition.
As with everything in life, there are NO guarantees, what we do know is that many of these dogs came from truly irresponsible breeders; there is another element that if a 'novice' is buying from an 'irresponsible' breeder', then the likelihood is that they are also not giving the new owners guidance on how best to rear their puppies to reduce any long term risk to their joints, so they could unwittingly exacerbate any conditions through ignorance :(
Hopefully by educating people into buying responsibly we can massively reduce the problems in our breed.
Just as with buying a car from a responsible dealer or a dodgy one, they hold less and greater risks of problems respectively, but just as you can be unlucky with the responsible car dealer, you can also be lucky with the dodgy one - and buying a puppy is sadly little different, other than you are dealing with living creatures.