after setting /etc/ftpaccess for guest use i found that the defaults are really disturbing, because there is no way to delete or overwrite any file even if owned for the guest users id as explained on : delete no guest,anonymous overwrite no guest,anonymous i think that setting a chroot home for a user explicitally changing its home with something like /home/foo/./ should make it to delete and overwrite files on its own directory (great for virtualhosts) it should be just : delete no anonymous overwrite no anonymous IMHO and seems secure enough
The use of this is for situations like ibiblio.org was a couple of years ago, where you could log in as anonymous for download, or as "upload" (=guest user) for getting write access to /pub/Incoming, where all files are automatically chowned to ftp:ftp. I agree that the other use is *far* more common and useful though, changed.