spammers harvesting emaill address from this list

[fbsd2]

It only takes 2-3 weeks after changing my email address I use on the list
before I start receiving spam on the new email address.
Other non-fbsd lists I belong to remove the posters email address before the
post gets sent to the list members.
Why can't this list do the same thing so the posters email address don't
show up in the archives on the news group servers where spammers harvest the
posters email address for targeting spam to?