[Uncle Bing]

I only ever use Calibre to put books on my Kindle Paperwhite seventh generation.
After I've read them I delete them using the Kindle.

I've now found hundreds of empty folders in the /documents folder
of my Kindle. They are the author folder and the book folder
of the books I have read.

I've done a quick test and Calibre of course removes both when you
delete a book from the device. But shouldn't the Kindle also do this?