I recived it too. 10 merits from unknown giver on unknown post.
Today at 08:14:23 PM: 10 from (Bitcoin Forum) for (Deleted/Off-limits/Ignored)
You could say that someone merited my post right before it was deleted. But as a person addicted from BTT i have multiple tabs with bitcointalk opened in my browser. One of those was my bitcointalk profile with 1535 posts and 599 merits.

And here are current stats (before this post):

As you can see amount of posts did not change. No post was deleted 10 merits was recived out of nowhere.
Edit:
LoyceV put it on the bottom of his post without attracting much attention,
Thanks to suchmoon I read it twice.
IT should have been like this :
This answers your question:Thanks to everyone who participated! If you voted in this event, you received 1 merit; if your caption appeared in the first table above, you also received 10, and if your caption appeared only in the second table above, you also received 2.
This should be enough to find it

Now i see it

To make this post a little less worthless I will add a suggestion to change "(Deleted/Off-limits/Ignored)" to "contest participant award" to awoid misunderstanding