Creating Criminals is an essential part of the melting pot.
An isolated indigenous society does not have nor encourage criminals. Any person either does something properly or they do it improperly and learn.
Anything, including a person, is either seen as a threat or as having something to offer. Foreigners are competition, and therefore usually a threat, but not 'criminal'. They might be killed, but unless they have intersected with the local culture there is nothing to 'punish' them for, aside from territorial offenses, trespassing if they are close.
Criminalization is how the melting pot keeps the conquered cultures at bay, and it is the opposite of teaching. In an early melting pot all of the criminals, prisoners, are of the conquered culture. As the disease grows, criminality balances the melting pot and expands into the dominant culture.
At some point superficial 'tribes' develop, like the rich and the poor. The rich generally want to keep both their wealth and their 'superior' status relative to the poor, so they are the initiators of wealth tribalism. In an isolated homogenous culture anything analogous to 'wealth' would be considered not a part of the person who found or had it, but apart from them. So a person who did not have whatever the 'wealth' was would still be a part owner of it.
"They one and all agree in regarding foreigners as an inferior race, whose customs, language, and religion they despise."