The appeal of communism to the people of countries with extremely high levels of poverty, like Cambodia (before the rise of Khmer Rouge, communist party that held control of the country for approximately four years), is the idea that this political and economic douctrine which is the extinction of social classes, which would bring about the liberation of the proletariat and would also give the conditions for those people to be able to leave the state of extreme poverty and be able to access basic human rights, such as having sufficient meals for human subsistence.
For those who have nothing, that is, that are in the most extreme misery, a theory that preaches that everyone should be equal in the society, and therefore have access to the same rights, has fertile soil to germinate support.