Because it appears to be his job.
Kazan is so obsessed, so emotionally dependent on it and so maniacal about Russia/Putin that there has to be far more to his unrelenting, non-stop, and radical posting on it than mere money.
He never stops, never lets up, and rarely even bothers to try to relate to the specific thread topic or posts that he posts to (or at), he just goes at it compulsively all day, every day.
Is that the building out of which the Russian trolls operate?