I’ve argued that although human language allowed egalitarian rules whose uniform enforcement would have greatly reduced the advantages to big-brain conniving, humans had the biggest brains of all to unequally
A good example of maintaining a tension in the society which in turn helps identify the bullies; read here psychopaths. From this resulting tension bullies learn to control their behaviour or suffer retaliation. This could extend to their untimely deaths.
I long thought this was the case. Maybe I read it somewhere else, but damned if I can remember where.