They are much faster in the US. If you ship it to them on a Monday, you'll likely have it back by Wed. or Thurs. I doubt they would have made you wait if you had taken it to a US Apple store.
On a lighter note, why does china even make iphone data cables? Its not even launched there?!!!
It's difficult to find anything that isn't made in China anymore. Even if it's an American made product, like say a Computer, at least several of the parts will be made in China.