I just bought 10k NX worth of these boxes and got 5 of the same hairpins in a row. It would be great if we were able to sell these in the Free Market since I can't do anything with the same pins. I'm sure there are people who are interested in purchasing these in the Free Market without having to take the same gamble. Also, we cannot trade these pins in for Avatar stamps.
I've talked to a friend on my buddy list who also opened these boxes, and she managed to get all hairpins without getting repeats. She also asked another individual who opened the box, and that person also did not get any repeated pins either. Maybe I was just really unlucky, I don't know. But what has happened has happened, and it would be great if I can at least do something with these extra pins other than delete them from my cash inventory (would be a waste of 2k NX per box). I wasn't sure if this was a bug or not, so I decided to post here instead.
Also, there is a text error when you hover over the Floral Hairpin Box in Cash Shop. It reads:
"It's a Foral Hairpin Box. Any one of 6 hairpins can be found inside."