[goodpoint]

> As a group expands in size, don’t the opportunities for an individual to amass wealth, and then translate that to power, also increase significantly?

Yes and no. Human societies in general have concepts of personal property (i.e. something you use, like your toothbrush).

Not all societies have concepts of private property that we have today i.e. something you never use but still control. This is a complex set of viewpoints with many conflicts. They changed a lot over time. Many are very modern.

E.g. you can become owner of land by adverse possession.

In many egalitarian societies a person hoarding excessive amounts of objects is seen as unhinged.