I'd say no as long as it's a breeder that I trust. I personally would not sell gifted animals especially if the breeder is a friend. If I raise em up and prove them out then I don't see a problem with not providing paperwork.
Example: If say Heather Wong or Adam Wysocki sent me hets without paperwork I would have no issues as I trust them and I know they could provide genetic info if needed later.
Example 2: If some random guy on KS sends me hets I would maybe try to prove them out but would not sell as hets.
Paperwork is only as legitimate as the breeder. Anyone can make up paperwork for their animals with pics and such.