that the sender hasn't understood the concept of BCC, in the past I have done reply-all with..
"Look at this fucking spastic who hasn't learnt how to bcc. Here is a lesson for them so they look fucking stupid and you if you didn't know about this handy feature. www.cs.rutgers.edu/~watrous/bcc-for-privacy.html "
(, Wed 19 Jul 2006, 7:10, archived)