It could work but not with the mindset of civilian passengers.  Think about a military style ejection seat for a second.  Those pilots are strapped into their setas far tighter than the average passenger.  The ejection seats I have seen (perhaps an air force or naval aviator could confirm?) also tie the pilot's legs and arms to the seats.  In the event of ejection, their purpose is to restrain limbs and not have the pilot's legs/arms flapping everywhere.  
Now you want to do that to a passenger that needs to get up and take walks down the aisle or have frequent bathroom breaks, the same passenger that has a laptop on the tray table, the same passenger that is not wearing a helmet or strapped into his seat with 4 point harness (or how ever many points an aviator has).  Let us not forget that you need to be physically fit (think about all of the fatties on an airplane for a moment) to endure an ejection seat which subjects the pilot to intense acceleration when the equivalent of a rocket motor fires underneath him propelling him out of the airplane.  Lets also not even discuss the fact that people will be ejected from an airplane into low pressure/low oxygen air that not everybody can survive.  And lets not even discuss that most people will not know how to handle a parachute or land one.
The only way to have an ejection seat is to replicate the conditions air force/navy pilots fly under and that also means giving passengers the same training.  That means the flight suit, helmet, seat restraints etc etc etc...  in short this will never happen!
Can you also imagine what will happen to the airplane when someone decides to eject in a non emergency situation?  Who would have control over the ejection mechanism?
Better off trying to design a crew capsule that can jettison from the airplane and even that is impractical and super expensive