Wow! A high school essay by a law professor (with a book published by UChicPress).
The reason “rule of law” works is of course because the harm done in a crime is vastly more than the reward to the criminal and so the punishment needed to deter it need not match the harm of the crime itself (even when the actual conviction and punishment are not certain outcomes).
A vengeance-based system of self-protection on the other hand requires being known for the capacity and willingness to provide a disproportionate response so as to deter through expectation of harm even thought the actual achievement of deterrent harm can never be certain. And because an individual does not have the profile of a state it is important to be extreme in the examples in order to gain a reputation as one who will and can respond forcefully.
We probably evolved in a context where self-protection was more important than it is now, so the pain I instinctively desire to inflict on those who offend me may well exceed that which I receive and there is no rational reason for it to be restricted be either equal or less, but in the higher interest of minimizing overall unnecessary suffering I accept that my immediate desires shall not be met and that the pain inflicted on offenders shall not exceed that necessary to deter the offense.
On the other hand, in some cases the probability of meeting justice is so low and the rewards of crime so high that there may be good reason for the penalty to be especially severe. So I have no objection on purely “justice” grounds to the death penalty (or even death by torture) for economic crimes committed in cold calculation of the expected outcome. (I do suspect though that there is a point at which the imposition of such harsh penalties may be undesirable as a result of the “heart-hardening” effect it would have on community as a whole.)