> This forces a COPY operation rather than a file MOVE if you drag-and-drop files into any Dropbox folder. Which means that everything in the Dropbox folder could be trashed tomorrow and nothing whatsoever would be lost.

This removes the main point of Dropbox, that when you edit your files they're automatically continually re-uploaded. If you're only making copies into Dropbox, you might as well just mount an SFTP server and save a bunch of money.