>I  think that  every  user has  the  right to  unsubscribe  from a  list
>whenever he/she wants.
 
It's not  a problem of  "right", but of not  being sure that  the command
actually comes from you.  Given a 20 lines exec and a  few minutes, it is
very easy  for a "smart"  user to REVIEW a  large and important  list and
zzzap,  signoff everybody,  clean and  neat. You  just need  to keep  the
output of  the REVIEW  on your disk  so that you  can resend  the signoff
commands every day, I mean,  otherwise people could re-subscribe and this
would spoil the fun.  With large lists there are so many  people who do a
REVIEW that it is practically impossible to locate you, since you need to
do the REVIEW only once.
 
  Eric