Newer cars these days comes with plastic bumpers with or with out having some closed-cell foam to absorb the impact.
if you think of a car suspension, it it taking load of entire car and it's occupants, still survives a 80 km shock due to running over pot hole or speed breaker.
energy absorbed due to impact is similar to frontal head on collision with a another stationary object.if y have been to port you can see small boats have tires at the point of contact to absorb the impact.
why can a par of struts in front and back of a car be used to hold the suspended bumpers like olden Ambassador and premier padmini. there can be soft materiel on top for pedestrian safety. such shock absorbers can adsorb far bigger impact then current bumpers and a sensor can sense the impact and automatically apply brake to reduce velocity of the vehicle.
This would lot of man hours and money involved in repairs of the cars aswelll, might be a new way of thinking about safety other than just crumple zones.