Well i think its pretty obvious why your steemit related posts are getting marked as spam...facebook is shitting their pants a little just because they KNOW that steemit is the social media of the future, the time will come when everyone will know what steemit is and FB will be left to rot (or any other social media platform not in the blockchain for that matter), they know this, just like the central bank/the goverment knows that cryptocurrency is going to replace fiat currency...fiat currency days are counted, the FUTURE is here already and they DONT like it at all.