There's a big difference between the multitude of mentally ill people and people like CS though. Many of the mentally ill don't go around destroying other peoples lives. You can't expect the public to react the same to such acts.
Given that medical understanding and treatment is so far away, i.e. not in CS's lifetime probably, we don't have the luxury of risking rehabiliation experiments. Neither do I as a taxpayer want to fund him for the rest of his life. So is a lethal injection a viable solution. What other practical solutions are there?
As for your rantings about desert life, frankly you've discredited yourself and I wouldn't choose to be in the same room as you thanks.