The explanatory tale is that some people have been collecting delayed or long-term rewards for altruism or other forms of self-controlled behavior.
The idea that altruistic behavior is a special case of self-controlled behavior is deeply intriguing.
The natural force promoting life into existence is related to the second law of thermodynamics lowering its selective pressure on self-controlled energy dissipative entities.
Altruistic patterns of acts are thus subsets of self-controlled patterns.
Where it is altruistic it will also be self-controlled (although the reverse may not be true).
The opposite question, whether a person may be altruistic without being self-controlled, however, is the one that concerns us here.
It seems clear that a person may be self-controlled without being altruistic.
It would still be unclear why all altruistic actions are self-controlled.