The present paradigm of neuroeconomics is too narrow in its conceptual setup in order to encompass all that is truly relevant and important in life. It starts from the assumption that the human beings are selfish and then goes on to study various anomalies (e.g. altruism) as something added to the fundamental assumptions. However, after some careful considerations it would appear that the fundamental assumptions themselves are very much restricted for the purpose of accounting for the development and maintenance of the self in the complex world that we find ourselves in.
Let's draw an analogy with the cycles of life here. In order to account for the fact that there are various forms of life on the earth, one needs to "doubt" the stability of existing life-forms and delve straight into the underlying vulnerabilities. If the life forms were not mortal, meeting their respective destinies in the struggle for life, there would not have been any evolution of the species.
The same can be said for the origin of the self. If the self does not "bleed" and "threatened" and even "destroyed" from time to time, it cannot really "evolve" in the course of an individual's life or over generations. "Emergence" originates in "emergency". Fury, envy, enchantment, bewilderment, hate, love, all these emotions that makes life such a complex and colourful experience is nothing more than reflections in one's psyche of the contingent processes that form the self in the interactions with the environment and other agencies.
Game theory, neuroeconomics, all these wonderful theories of the origin of human cognition and behavior are just scratches on the surface of the gigantic mass of mentality out of which our humble every day life is formed.