True - but as has already been discussed on multiple breed threads - someone can buy directly from John Doe or import 100% something and then go and ruin the breed totally. Some breeders import only one pair and then breed and rebreed that same pair and their offspring until inbreeding rears it's ugly head. So there can be "issues" all the way around when you buy birds. I remember when Marans were all the fad and suddenly birds hatching with web feet started showing up - coming from certain "breeders" and now it's carnation combs. And, even though my French Black Copper Marans came from the eggs that came from France it does NOT mean they meet SOP anymore than someone else's birds who have never heard of France. I think you should buy from a reputable breeder who has pictures of their birds or allows you to visit their facilities. Then on down the line (say a couple of years later), it is you, not the original breeder who can take credit for prize winning birds or face the problems you've caused by inbreeding or mixing other lines into the mix, etc. etc.
What I'm saying is that the original breeder and country of origin only go so far. What each new breeder does with that stock is what's important. I believe English Orps should be affordable and allow as many breeders as possible to own and work with this beautiful breed. As such, I sell my chicks for $15 each, not $65-$100+ each. With all my breeds, I show pictures of the parents and of the offspring I've raised from those parents but it's up to each individual to then improve on (or ruin totally) the work I've done in the 3-4 years I've been breeding them.
Last I heard, when you enter an Orpington in a show it's entered as "English" or "American". It either wins or not based on how it meets SOP and how it ranks when compared to the other entries. They don't ask is it "100%". That's not a terminology in APA SOP books or any breed book of any species. Also, as has been pointed out, many people just want a beautiful bird. They have no intention of ever showing the birds and they have limited funds. I try to help as many of those people own this beautiful bird as I can.