Death Penalty and Drug Addicts in Prison

I personally don’t believe in the death penalty, I think that it is useless to confine a person for years and then just kill them. We justify that the punishment should fit the crime; so if you kill someone, you disserve to die. But notice we do not use that policy with other crimes. If we murder murderers, it would be logical to rape rapists, and torture torturers, but do we do that? No, why not? It sounds good on paper. But we can’t do that to people because it is too inhumane, so we have to do the worst possible thing to punish the criminal. People claim the worst possible thing we can do to these criminals is to take their life away from them, but for me that seems as if we are letting them off scot free. If they’re dead, then there is no possible remorse for the prisoner to have.
Others claim that it is stupid for us to pay in taxes to keep these criminals alive. This brings me to another idea which is the basis of my views on Capital Punishment. Drug addicts make up now make up a majority of those who are currently in prison. And though rehabilitation is available, the average inmate only stays 80% of their sentence, so a vast majority do not finish the programs and leave prison and come right back for the same reason. Drug abusers should not be imprisoned; they should be put through mandatory rehab. With the money that is saved by keeping drug addicts out of prison, we can afford to keep the real criminals in prison for the rest of their lives and not let them have the satisfaction of dying quickly.