[squid-users] What closed lists for?

From the FAQ:

1.9 What Squid mailing lists are available?

squid-bugs@squid-cache.org: A closed list for sending us bug reports.
  Bug reports received here are given priority over those mentioned on squid-users.
squid@squid-cache.org: A closed list for sending us feed-back and ideas.
squid-faq@squid-cache.org: A closed list for sending us feed-back, updates,
  and additions to the Squid FAQ.

A *closed* list for feedback and FAQ? Why? Being a long time
linux-kernel reader, this seems strange to me... do you have
such a high traffic folks?

--
vda