I decided to opt out of this event because I did not want noobs attacking my castle. When I woke up this morning, I decided to admire my profile and I noticed something. While having the opt out spell active, I still have 10 shards. The spell was supposed to take my shards away but I still have some. Did I break the game? Oh, I bet you guys would love to see my picture again! ^^
I suppose they didn't bother with getting rid of the daily shards as they aren't enough to get a reward anyways. Less work for devs to just clear out at the end
You'll still receive the 10 daily shards, but you won't be eligible for rewards at the end of the event.