Hi @mindreader! I appreciate your curiosity, you asked a really good question. To be honest, I didn't know why this had happened, but I looked into it after I saw your question. It seems that it has something to do with the voters' reputation and their reward share. I'm not sure if I understood it correctly so you should maybe check out this post: https://steemit.com/steemit/@arcange/what-is-steemit-reputation-and-how-does-it-work Thank you for your comment :)