Well, the posts are upvoted by the SmartHive team for Steemit. It is all decentralized and there is no central governing body. But as they are all very active and interested in pushing the project forward and the rules clearly state unique information I assume they check the posts for plagiarism adn false info. But I have no data about that. You can ask yourself in the Discord channel: https://discord.gg/VMwh3TR

I have not seen Steemians making good money with stolen content as there are tons of mechanisms exposing these posts.