You know, “the info provided in this document is confidential and intended for the party…blah blah blah…if you have received this in error…blah blah blah…”
Are they necessary? Do they truly offer some form of protection? Against what?
They seem, to me, like ridiculous paranoia approaching the level of urban legendhood (“yeah, my neighbor’s aunt got fired because she didn’t instruct the receiver of her email to destroy it without reading it if the message was not received by the intended recipient”)