Why do people laugh at FLAT EARTHERS! (Patreon)

...honestly I'd dodged this subject for so long since its so hard to tell reality from parody.  But its just crazy surreal to watch people seriously debate things that have been known about for hundreds of years, and are trivial to verify yourself.  Like for instance if the moon emits its own light.  Even a kids telescope will show you the shadows on the moon, and you can watch the shadows change over the course of a night, and certainly from day to day.  You can watch lunar mountain ranges emerge from the shadows and go back into them.

In this case these flat Earthers seem to even deny gravity. But even if you deny 'gravity' they surely must at least concede that objects fall when dropped.  After all that all you need to understand is a little of the kinetics of hard spheres and you can understand how planets hold onto atmospheres!