Can anyone answer this question about Steem Now?

I believe most steemians must have heard of Steem Now.  

It is a tool that, among other things, lets you check your daily Steemit rewards, and more specifically “Curation today”, “Author today”, “Curation yesterday”, and “Author yesterday” earnings. 

Image originally uploaded by francousqui on Flickr.com and reused under CC0 1.0 Universal (CC0 1.0) Public Domain Dedication Creative Commons License  

Recently, I have noticed that although I haven’t been directly rewarded for any of my activity (as I didn’t write any posts or comments, or my posts or comments did not get any upvotes and rewards), Steem Now showed some “Author today” and/or “Author yesterday” rewards. 

This happened after more than one month passed from the day that I had any type of activity (posts or comments) on Steemit. 

How can this be possible, I mean getting rewards while being inactive? These rewards do not show in my wallet. 

Does anyone have any idea?