You shouldn't. That's the trick - and the reason, why we use it.
To send a message to (in this case: many) people,
that don't need to know of each others.
The reasons for that are obvious.
No, that isn't the trick. Removal of the BCC is optional, and not all
systems do it. Nor is the reason that it should be removed obvious. In
a business setting with real carbon paper, the Bcc recipient always saw
to whom the memo was addressed. The only required protocol is that the
primary addressees not know to whom a blind copy is sent.
If you want to guarantee that no recipient knows to whom else the
message is sent, send separate messages, or know well the mail software
used by each, and by all systems on the route the message takes.
--
Rik Kabel Old enough to be an adult
rik(_at_)netcom(_dot_)com