To a Machiavellian, the benefit is implicit, because there is a moral obligation as a leader to provide structure and security for the masses - i.e. it is the right and role of the strong to rule the weak. And strength is demonstrated by the reach of control exercised by the ruler.
Alternatively Thomas Hobbes, John Locke and Thomas Jefferson would argue that the sovereign protects the weak, so that we can all co-habitat, transcend the "state-of-nature" and allow for the collective efforts of all to flourish. The state-of-nature is identified as "might equals right", because in the state-of-nature everything exists in the "commons" and ownership is only exemplified through direct control. In order to lay claim to anything requires a constant defense. However, to form the foundation of society, a sovereign is created through the concession of a portion each individual's power (unencumbered freedom) into a single entity that then represents the collective might of the community. This collective concession creates equality amongst its members. The strong and the weak are nominalized into citizens, unified by the understanding that the collective output of a society exceeds the sum of its individual parts.