All that is nice but a store providing a receipt and a "breeder" providing paperwork are two different things.
You buy a microwave and it does not work you return it the same day or within the next 30 days (which is standard for returns) and you get your money back or an exchange. The store will not be gone in 30 days.
You buy from a breeder with little to know rep (and those days with social medias they are plenty), you get a nice piece of paper telling you all about genetics of your animals, you raise your animals breed them this could be taken anywhere between 3 to 5 years or more and the animals do not prove and now the "breeder" has vanished (like many do each year), what do you have left an nice piece of paper.
The majority of well known REPUTABLE breeder will not provide paperwork what does that tell you? A piece of paper means VERY little.
I provide paperwork however the reason I do it's to ease the re-sell of my animals should one of my customer sell their animals, and I can tell you that even if I did not provide paperwork I would still guarantee my animals.
Again the paperwork is only as good as the breeder is.