Interesting info. I've also been looking in to it a bit more, and found this reddit post from the CEO of Kraken: https://www.reddit.com/r/Bitcoin/comments/41vhzz/im_jesse_powell_cofounder_ceo_at_kraken_ama/cz60can.

It seems like he accepts that these users should have received something in return for the shares, whilst also pointing out the shares were sub par when compared to a proper VC round (as you said). However, he does then say he will reach out to shareholders in the future (that post was 3 years ago), and that doesn't seem to have been done.

Although likely perfectly legal, it seems a bit disingenuous to me to be selling fresh shares without sorting out the issues regarding these older ones first.