You seem to have an idea that indigenous societies are/were simply a more simplistic analog of our own society but the reality is that it is in entirely different and equally complex social structure.
Many Mesoamerican cultures were egalitarian as well, a tradition that lives on today in the Zapatista Autonomous Municipalities.
Trying to characterize indigenous people as "cannibals" or "savages" is merely a failure to understand the profound nature of these cultural difference. Ritual cannibalism or human sacrifice are not analogous to oppressive structures in modern industrial society.