I've accidentally shown mine before. I was in a liquor store buying some tasty beer and accidentally handed my CHL to the cashier. After too long of a pause I looked at her and she just said "sorry, I dont get these often" then smiled and handed it back to me. I walked out with my six pack pretty embarrassed, but hey, it worked! At least I didnt hand it to the TSA guys at the airport, I'm sure that would have been fun!
I don't intentionally use it as an ID though, and I havent been in a situation where I've needed two ID's in a pretty long time.