It's because of survival pressure :-/ I think we are falling in an unprecedentedly large-scale negative-sum prisoner dilemma.
This situation may be naturally evolved, or may be deliberately shaped by people or institutions. In any way, negative-sum can drive people to do irrational decision because the game is not beneficial in all cases.
This situation may be naturally evolved, or may be deliberately shaped by people or institutions. In any way, negative-sum can drive people to do irrational decision because the game is not beneficial in all cases.