those are indigenous people who go there. actually go to mexico and you'll see the farther south you go the more indigenous it gets. there's two type of mexicans, 1.) the "indian natives" most are uneducated, dont even speak spanish, work in farms with no electricity, running water, etc. the second kind of mexicans who are generally either mixed or more european are in govt, military, speak spanish, have running water, electricity, and jobs, they don't leave mexico and if they do go it's to buy stuff in malls in America. what comes through the border are the lower caste members of mexico who simply aren't allowed to be a part of society, they come to the usa because the U.S.A doesn't treat them like lower class trash and they can get jobs here. actual mexicans like mexico and never leave.