This is an elliptical question which when expanded is: Why are we stuck with capitalism and a representative democracy?
It is analogous to asking a slave: Why are you stuck in slavery?
My answer is that this state of affairs is the result of conquest, a position which was expounded by two sociologists: Ludwig Gumplowicz (1838-1909) and Franz Oppenheimer (1864-1943).
According to Franz Oppenheimer in his book, The State (1914), nomadic pastoralists can, and do, form hierarchies of dependence because animals can be lost to predators or disease, or some natural disaster. This causes those in distress to depend on the more fortunate and industrious. Herders, in addition, having to maneuver and protect their animals develop athletic skills so that they are indistiguishable from warriors. And as soon as there is any property which can be acquired — either of another herder or a sedentary farmer, this is an incentive to take it by force. And then he lists 6 stages of forcible appropriation. Using the analogy of obtaining honey, he divides these into the method of the bear — whereby the honey is obtained through the destruction of the hive, and the other 5 methods are those of the bee-keeper: taking only the surplus.
“The six stages Oppenheimer describes may be conveniently epitomized as follows: (1) extermination; (2) appropriation of surplus; (3) tribute-giving; (4) occupation; (5) regulation; and (6) amalgamation.” [Chapter XIX: Struggle over “The Struggle for Existence”: Social Darwinism, Pros and Cons, in Howard Becker and Harry Elmer Barnes, Social Thought from Lore to Science, Vol. 2 (1938), p. 726.]
Analogous to land nomads there are also sea nomads, such as pirates and the Vikings.
Oppenheimer stipulates that obtaining the necessities of life by work or free exchange is to be called “the economic means”; whereas anything taken by force is to be called “the political means.”
But really, the anthropological or sociological question of how States originated in prehistory is superfluous, since in historical times it is war, conquest, colonization, and extermination which have propelled us to our present worldwide condition.
I am aware that there are other theories of state formation. These can be classified as coercive and voluntaristic theories. Whatever happened in pre-history, it is clear to me that the historical record is of a coercive type of state formation.
Below are some relevant documents — readily available on the Internet:
Franz Oppenheimer, The State, 1914.
William MacLeod, The Origin of the State, 1924.
Robert H. Lowie, The Origin of the State, 1927.
R. L. Carneiro, “A Theory of the Origin of the State”, Science. vol. 169, 1970: pp. 733–738
Elman Service, Origin of the State and Civilization, 1975.
R. L. Carneiro, “The Circumscription Theory: A Clarification, Amplification, and Reformulation”, Social Evolution & History, 11(2), (2012), 5–30.