Well it's more to do with the unreliability of the sources we use. It is a fact that Bird in a bird in a bird has been in existence in the UK since Tudor times yet it would be hard to garner that from wikipedia.
The majority of Americans are descended from Europeans, a very large proportion being English so it would be rather strange if all recipes and food traditions were simply left behind.
It's as American as Apple Pi...
Doing some additional research, some version of a bird stuffed bird goes back to Roman times. I seriously doubt that anyone copied anyone. It is the kind of novelty dish that was probably invented separately a hundred times -- or more.
I knew this history of the Turducken because of my interest in Cajun foods, and because my ex-wife was a huge Emeril fan. I learned about it watching Emeril Live with her.
Yes, there is a history of European inspired foods in the US, but we Murcans do occasionally do something original, although it is usually something trivial like, oh... walk on the moon, or invent the mobile cell phone.
We are WAY off-topic. Sorry SomeStrangeMan.
CD