I don't know... If it was a widespread faulty issue with the 3DS, wouldn't NewEgg be hurting more than amazon to not carry the device either? Amazon video game deals have been pretty lackluster starting last year. They might have pissed off more than Nintendo from getting a deeper wholesaler discount, while other items(not video games) I purchase from amazon are pretty competitive priced. You know something is brewing when a smaller retailer like NewEgg is owning Amazon on pre-order credit promos.
I hear it's a bitch to return something to newegg, and their customer service pales in comparison to Amazon's. not to mention I imagine that Amazon probably got 100x the traffic for 3ds hardware sales than newegg, and is likely by far the #1 online video game retailer. So the fact that Amazon is having issues with the minor flaws in the 3DS whereas other companies are not is not surprising to me.