They know I don't even own one, so their expectations are forced to zero. And I know I'm not so narcissistic that it can't wait until I see them. Or find a regular telephone.
Mercifully, you'll never be forced while washing your hands at Seattle-Tacoma Airport after a flight to listen to me trying to close a business deal while I'm sitting on the can. And I am perfectly capable of selecting a brand of toilet paper without needing to spend one of my lifelines consulting anyone via a cell phone.
Mobile phones thus wouldn't solve any problems for me, but they would create a whole new set of others. And I'm the one who defines what my problems are and which might benefit from a technological solution—not all of the gadget-maker's marketing departments.