I don't agree.
There are very large numbers of Central/South Americans who come to Cali, largely unskilled, and they occupy the biggest part of the economic underclass.
Think of how many are not even 'on the books'? I'd argue it's very difficult for an undocumented person to make that much.
It's not a 'moral' statement, it's just a reality of the blending of people from different civilizations in one pot.
Large scale migration from poor countries will definitely be a factor.
And as one commenter above noted - the 'weather' does as well.
Nice weather attracts more vagabonds. This is true in Canada s well, BC has way more street people than Ontario where it's extremely cold and extremely uncomfortable for street people in the winter. Again, not a moral statement. Just fairly rational human nature.