The Non ped title given to whippets is confusing but as you said, their pedigrees are well known and documented, so other than the KC accepting the standard differences, I don't know what more you could ask for.
Greyhounds are considered endangered by the KC, in the 5 lowest registered breeds, when thousands are bred yearly.
When you say pedigree, it gives the impression of a 'pure' bred, a recognised breed. When any dog can come with a 3 or 5 generation (or more) pedigree.
You could ask the same between many different breeds - the Labrador for example, being the most registered breed ag