Your emotions are normal. I like the idea of not just taking a picture of the plate, but immediately emailing it to your home email address. The act of photographing someone will run risk of infuriating them, but having the ability to say "it's been emailed home as evidence and my husband knows to look there is anything happens to me" can have a sobering effect.

Finally, I confronted a similar issue a few months ago...and am trying to be prepared with humor to disarm situations like this:

http://forums.teamestrogen.com/showthread.php?t=23477