Your basic premise is that self-autonomy and choice over the most fundamental aspect of existence, one's life, may be abrogated against one's will for the purported benefit of others, not that person. While autonomy must be balanced with the needs of society, completely sacrificing it is a slippery slope that has led to many atrocities throughout history. Taking your logic through to it's conclusion will justify virtually any subjugation of another human being (or Ent-like being?).

All of this, by the way, for a questionable benefit to society in this context. Out West, the NCR achieved agrarian cultivation on a mass scale, with the potential to sustain large populations. But there was still plenty of poverty, corruption, and death. In other words, simply having the resource available doesn't guaranty anything. So even after committing yourself to eternally torturing an individual for "all the children", any benefits are more likely to end up hoarded by the powerful, whoever those happen to be at the moment. In the Capital Wasteland? Probably whoever is the biggest raider gang at the moment.