I'm the fool who still doesn't get it, and when I hear someone talking next to me, I turn to them and say "What?" Only to find that they're on the phone.
*sigh*
I can definitely identify with that! Have you ever had conversations with people you know and didn't realize they were talking on their cell? I have and it's really embarassing!
Them: Hi!
Me: Hi there!
Them: How are you doing today?
Me: Oh, blah, blah, blah...
Then you realize they're talking to someone on their cell but you didn't notice because they weren't completely facing you head on so the phone was hidden from my sight.