Maybe there are a few harmless eccentrics, then again you could see them as lying dishonest individuals who are in it for the money. The trouble is they post their videos on youtube & suddenly there are a lot of young impressionable minds being taken in by all the rubbish like NASA is lying to you its all CGI, personally i do not have time for flat earthers & its much more widespread that it should be than if it were just some harmless eccentrics.By the way, I personally don't class the flat-earthers in the loony/conspiracy class. From what I've seen of them generally I'd mark them as harmless eccentrics, who love winding people up. I rather like them.
Here's a couple of examples from the tube :
Then you have sh*te like this, buy a t-shirt pay to listen to these idiots.
The 2019 Flat Earth International Conference. Join us November 14-15
My point is it is not harmless.
Even when the prove it to themselves the still deny the truth of the matter.