I think when cell phones first came out on the market, it was a status thing for a lot of folks. "Hey, I'm important, I have to carry a cell phone." And I suspect that some folks back then would take delight in conversing on their phones in public to show how important they were. But now, just about everyone owns a phone. And most folks using it in public settings are just plain rude, not trying to impress anyone.
Now for my Barney moment. At work I have a digital phone (Cisco). If you lift the reciever up long enough, the dial tone will stop, and the ear piece is quiet. With our old system I would on occasion take the reciever off the phone and jus set it on the desk if I didn't want to be disturbed. Anyone calling would get a busy signal. Well the new digital system doesn't work like that. You do that, and your phone will still ring if someone calls you. I didn't know that.
Any way, one day I saw a feller I didn't want to talk to headed to my office so I picked up my phone pretending to be in intense conversation. He came in and sat down to wait for me to finish. Well I figured I could out do him so I had this great pretend conversation going on, when all of a sudden, you guessed it, the dang phone started ringing. Well I was quick on my feet and told my pretend caller my other line was ringing and had to answer it. I never did find out if my visitor figured out what I was doing, but he did eventually leave so I guess the end result was all that mattered.