I think it's more like

since indigenous population has [a higher cost of living]

I've heard a bunch of stories about temporary farm workers making more cash here than they would in their home countries, even though they're still paid poorly by Canadian standards.

There are a bunch of downsides for them: employers at home don't want to hire them, since they expect them to leave when the Canadian farm season picks up; they don't see their families; they're "abused by the owner class" (as you say).