I don't know how practical it would be. The last time Nevada executed a criminal was 2006, and that guy killed two people (one of whom he graped first). I'm not claiming a jury wouldn't recommend capital punishment, but given the large time gap since the last execution and the comparative circumstances, I don't think they'd be as likely to make that recommendation.
Practicality aside, I don't think the death penalty does anything useful on principle. Even if the perpetrator is afraid of death, they get a relatively gentle death via lethal injection (the only legal method in NV). No one gets justice from that. A dead person cannot learn anything, suffer shame and embarrassment, or truly experience the consequences of their actions. Only a living person can do those things. Maybe these perpetrators feel no remorse, and maybe they won't actually learn their lesson by spending life in prison. However, they will know they're trapped forever, and that will be their reality until they die decades later. That is a fate worse than death itself.
Our laws are intended to punish the criminal and protect us from their bad actions.
Feeding them until they drop dead punishes us. And most likely they would get out early and find someone else to Victimize. We do not need to be punished by spending large amounts of money being their caretakers either.
I say the death penalty has purpose in this case.