I left NZ with a pile, intending to return with same pile. I didn't want to pay duty on reimporting my pile so I went to see Customs on the way out and they slapped a sticker on it. I don't recall if they checked it or took my word for it when I came back.
The sticker was nothing fancy a but a real bear to remove. No way it would be possible to peel off one bass and put on another.