the hatchery birds do NOT meet the standard and I have yet to find one that does. They need to BREED TRUE which the hatchery birds will not do. If you take one that may look like it meets the standard and breed it to that variety, at the very least you get leakage of other colors which will disqualify it as a true ameraucana. Araucana is a whole different breed which is rumpless and has tufts. The biggest reason for being EE is because the birds the hatcheries use to OUTCROSS to increase egg production, which is a whole 'nother ball of wax....
ETA- I have a blue wheaten ameraucana roo over my free range flock. He has black, splash and w/bw hens....all TRUE ameraucana but I still tell people that get eggs that they will be easter eggers (although they will get some pure wheaten/blue wheaten)....because they are "mixed" colors. What makes mine different from the hatcheries? Nothing, because they won't breed true(except the w/bw)
I second everything klf said, and would only add that in general, it is "safer" for us to call everything that comes from a hatchery as an "Ameraucana" an EE, because you literally never know what you are going to get, and like klf said, they will rarely, if ever, breed true.
I have two hatchery "Ameraucanas" that don't even carry the blue egg gene. One lays a pinkish egg with white speckles on it, and the other lays a brown egg. They both have very full beards and muffs, nice tight pea combs, and slate colored legs. One of them is cream colored with blue beard and red leakage on her feathers, but when I breed her to my lavender roo, I've gotten all BLUE chicks...