They wouldn't, which is why I think whoever is selling is retail, or some group or entity that was paid in shares a while back and is either now able to sell them or perhaps even some tax selling. But there is no conspiracy here and MMs don't take down stocks to load them.
My post is only my opinion, I recommend you always do your own DD! I am not a licensed broker or a professional by any means, so take what I say as entertainment value at best.