it's not there to satisfy revenge. it's there to remove dangerous elements -- specifically psychopaths and extreme sociopaths -- from society. why should society support an element that seeks to take individual lives without conscience?
Are you playing devil's advocate or have you done a complete 180 from a few years back?

I remember us discussing this (on opposite sides of the argument) pretty heatedly on GA. This was basically my stance -- that the dispassionate, even-handed, and utilitarian application of the death penalty serves the best interests of society.
Also, to elaborate for the sake of others who have not heard my views on this before, I only support the DP in cases where there is an overwhelming abundance of evidence (e.g., multiple eyewitnesses
plus circumstantial evidence
plus DNA/video etc.; the ideal case would be a hostage situation that ends badly for the victims). I would not under any circumstance endorse the DP for weakly supported murder cases, however egregious the act was. It should be noted that I am also perfectly fine with life imprisonment instead of the DP, as possible recidivism is ultimately what I'm concerned about.
For those serving a life term, I believe that prison life should be minimalist (which it currently is not). One can argue that something a cut above subsistence level would be fine for those convicted of lesser offenses, as you don't want them to become unduly hardened upon their eventual release, since this might contribute to recidivism. I do believe in things like education and vocational programs for inmates who are not serving life terms.