We're all thinking it was a stupid move of them, but can we really say that with certainty? Likely none of us were involved in the scene in 2013, most became involved in the last year. Probably everyone reading this post would have thought bitcoin was never going to go anywhere back in 2013, and that amount of bitcoin was only worth a few dollars back then. Not such a crazy idea to destroy it if that's your train of thought.
RE: 5 Years ago, Wired magazine called Bitcoin an abstraction, destroyed their wallet keys and now can't access $120k worth of Bitcoin