Marcel Mauss's The Gift is a classic of the field. His analysis of how "primitive" societies are based on reciprocal gift-exchanges is completely counter-intuitive to people who are only accustomed to living under Capitalism, where the logic of commodity exchange is the norm.

David Graeber's Debt: The First 5000 Years is a very broad book that touches on many, many topics but also shatters many myths about "how people behave" by discussing the different ways that different societies have engaged with the concepts of "debt" and reciprocity over a period of 5000 years. Graeber analyses social relations from the POV of three competing moral principles: "Communism", "exchange" and "authority"; and argues that the three principles present themselves to different degrees and interact with one another in different ways in pretty much all societies. His point about how many social relations in the capitalist world are already "communal" (such as for example, raising a family, co-workers sharing resources to get the job done, etc) and how it is outright bizarre or even offensive when people try do away with this "baseline communism" is particularly eye-opening.

James C. Scott's The Moral Economy of the Peasant: Rebellion and Subsistence in Southeast Asia is an analysis of peasant life and rebellion in, uh, Southeast Asia. He point that in these societies life is predicated on the fact that starvation is the worst case scenario, so the social order is built around minimizing social risk for everybody and establishing long-standing ties of reciprocity and reliability rather than "profit-maximization" or competitiveness, and that attempts to impose a logic of "profit-maximization" or market-based insecurities upon these societies has led to catastrophic failure and severe resistance (even when they supposedly increase the income of the peasants, they lead to social polarization, class struggles and social instability/conflict). He points that the poverty in many peasant societies in the world today does not come from their "failure to develop" but by the contrary comes from the attempt to forcefully "develop" them by integrating them into the global world market.

Though not an anthropology book Elinor Ostrom's book Governing the Commons: The Evolution of Institutions for Collective Action is an analysis of how many societies have sucessfully self-organised to exploit and maintain common resources on a self-sustaining and mutually beneficial basis, and what is the basis in game theory for how these projects succeeded. It shatters many myths about "how humans behave" by showing that people can work together to maintain a common resource (contrary to ideas like "the tragedy of the commons") if they are given an adequate framework to do so.

If you know any person who is prone to making blanket statements about "how humans behave" or about "human nature" that are based on how we behave under Capitalism, show them any of these books and it will be an eye-opening read unless they completely fail to throughly engage with the work.