As Judith mentioned, you need not subscribe to a list to
be an owner.  She also mentions that it is a good idea
to read/scan your list e.g., what did you do if a frustrated
user is trying to UNSUB by e-mailing the list instead of
the LISTSERV?  Of course you need need actually be subscribed
in order to read your list e.g., you might be viewing it
via Usenet or the WEB.
 
/Pete