I came across this link with “Ten Commandments of Cell Phone Etiquite”.
http://www.infoworld.com/articles/op/xml/00/05/26/000526opwireless.html
I took comfort in the fact that I keep those “laws” fairly well.
Particularly the “Thou Shalt Not Wear an Earpiece when Thou Are Not on the Phone”.
I have a bluetooth, but feel quite self concience wearing it outside of my car even when I AM on the phone.
I will, on occasion, wear it around the house when I have downloaded a book from Audible, or am watching some video on my phone. Otherwise, I am pretty quick to throw the headset in my coat pocket when I get out of my car.