Many of those people you see with the cell phone glued to their ears, don't have a choice. This is true for women, in particular. They are talking to their life support technician who is on the phone telling them to, "inhale....., exhale....., inhale....., exhale....., breath in....., breath out......" So, you see, if they were to hang up, they would surely die.
I personally don't understand all the hoopla over using "hands free" devices. To me, it's the conversation that is the distraction, not the cell phone.
And, don't get me started on those "Borg" looking bluetooth gizmos with the blue LED flashing light... "Assimilate, or be destroyed.." :nono: