It has a dozen listings there, most or even all of which are completely unuseful to me. If I could replace them with links to playlist files, that would be better... but even just being able to remove them so it looks less cluttered would be a solution as far as I'm concerned.
It turns out that items on the left-hand side that are underneath the "Internet" top-level menu are just scripts. If you navigate to the install directory for VLC, and then into share/lua/sd, you will see a corresponding script for each submenu entry. Deleting these files will remove them in VLC (but be sure to try them first to see if you like them!).
The other entries in the menu seem to be unchangeable.