It helps when migrating, or just performing actions on a live site that might affect users' information.
What I didn't understand is when I exported the userlist (users.csv), why didn't it export the password hashes with it. The answer: The passwords are stored in the core users list that comes with joomla so it is referenced there. If you need to mess around with the joomla users list, I recommend using the original JUICE, that deals with it.
Otherwise, great utility! Does everything at a drop of a click! Hats off to the core team!
I can add the password to the save but it will be hashed. My concern has been that people will try to reload a hashed password. The challenge is that with continual changes to the hash, this could get into really messy things. It is NOT possible to export passwords in a clear format. If you have specific suggestions, use the joomla code forum because I would be interested.