So, every once in a while when I plug in one of my USB sticks to my PC a folder will appear labeled .100 Trash or .1000 Trash. Something like that and if I open the folder it has everything that I have previously deleted from my USB drive? What is going on?
Welcome to nixCraft forum!
May I know your Linux distro and desktop environment? The .trash folder is created by default, and also it is hidden by default. So you must have enabled the display hidden files option in your file manager. There is also a lost and found folder. Can you check for the hidden folder settings? Here is how it looks on Gnome desktop:
Second, you need to empty .trash manually as this is created to avoid accidental deletion. So go to .Trash folder and click on the Empty button:
Now try it again. I hope this sorts our your issue.