It should be noted that there are some, such as myself, who choose to keep their email addresses hidden. Also, if the message was sent by that means, it would likely mention BZP somewhere in the title and open with something along the lines of "<your display name>, <spammer's display name> has sent you an email". It's been ages since I've received an email sent through BZP, so I don't remember the exact wording, but it's something like that.