They fear their loss of power over us. We could kill them, rend them to shreds and they would accept that more willingly since death is an eventuality.
But for them to be subservient to us? For all they worked and striven and sacrificed for to be taken away from them? For them to be castigated to a class below the middle, below the low and the poverty stricken. That would hurt them the most in their final days before going to Hell.