Anybody can write out a pedigree - it is just a list of names of ancestors.
Problem is, if the parents are not registered with the Kennel Club you have no way of knowing if they are even purebred.
There is a thing called the Dog Lovers Registration Club that you can pay your money and register anything from any parentage - no-one checks and people have been fooled into thinking they are buying a 'registered' pedigree dog.
Often breeders give a pedigree with a dog, but not the registration, although I have sold several where the new owners have never transferred the registration to their names, so as far as the KC are concerned they still belong to me.
I would advise anyone to go to a reputable breeder found through the breed club, make sure they are pedigree and registered with the KC and transfer them to their own name. I hate it when people say I am not bothered about papers I only want it for a pet. This gives the puppy farmers an excuse to sell substandard dogs to people who think they are getting something on the cheap often with no health checks done on the parents.
A dog could be with you for up to 15 or more years, so make sure you get one that is bred and reared properly and will live a long and healthy life as far as it is possible to predict.