Difference between pet and show quality is just how well it matches up with the APA Standard of Perfection.... if you are in the US that is. "Show quality" can also be some what determined by trends in the breeding too, as some like HUGE crests and HUGE leg feathers, while I prefer the modest crest and lighter leg feathering. However, I don't raise show quality.
Unless you are showing, doesn't really matter what they look like per se, as you can still keep them as great pets.
So in short, a pet quality silkie IS a real silkie, just as much as a show quality or breeer quality silkie is still a real silkie. It just doesn't fit with the breed standards.