I know that a lot of computer equipment is shipped to Asia to be either re-used or recycled. I'd almost lay money down that one of the companies receiving stuff has someone (or several) that goes through the fresh stock and looks for something that would bring a nice profit if it were resold on eBay and such. Fro things I know about the recycling market it wouldn't surprise me a bit if these were either once sold as scrap or were part of a large lot of cheap used electronics.

That's not to say there's anything wrong with buying cool parts from (seemingly legit) Chinese sellers. If they can make a profit by selling hard to source items to international buyers, kick patooter!

EDIT: How come s.c.r.a.p. tripped the content filter? Must be because ot the last four letters, and if so, the filter is a bit too sensitive.