Why did Rousseau describe early civil society as benefiting rich people more than poor people?

In his Discourse on the Origin of Inequality, Jean-Jacques Rousseau argues that early civil society was established through a fraudulent social contract that primarily served the interests of the wealthy.12

Rousseau explains that the introduction of property created a need for law and government to protect possessions. While this system offered a degree of peace for everyone, it disproportionately benefited the rich by transforming their de facto ownership into legally recognized, rightful ownership. Consequently, this arrangement institutionalized inequality, as it provided the wealthy with the protection of the state to secure their assets while keeping the poor in a state of dispossession.12

Rousseau viewed this as a fundamental departure from the natural state, where the earth belonged to no one, and he contrasted this "fraudulent" contract with the genuine social contract he later proposed in The Social Contract, which aimed to recover true political liberty through the general will.12