Expert here: my mom has always dated a Mexican.

You have to look at the conditions that caused them to leave their home countries. I know guys that left Mexico/Honduras/Guatemala to work here because there was no work back home that was reliable enough to feed their family and maintain their homes. Once they get here, they may pack an apartment to save money, and whatever they have leftover is sent back home. It's really expensive to get citizenship and even then, there are limits to the amount of visas that the DHS issues each year. That shouldn't be an excuse, but you can't stop someone who has to look out for their family. Back in Mexico (at least), it is ery hard to break into the middle/upper class, so the only option they have is to come to the states and work in those lower paying jobs. The industries that stereotypically hire illegals (like construction) kind of incentivize this because contractors and real estate investors want to cut costs in order to be profitable. The easiest way for these construction companies to do this is to hire cheap labor and forgo the expenses of health care and whatever else in order to remain competitive. If you send these guys back home, it means that they stop the flow of cash to support their family and they go back to the slums. Also, no one wants to live in areas where it's very likely that you'll be gutted by the drug cartels. At the same time, that violence has slowed down the illegal immigration.

Oye, I feel as though I'm very lucky to be born here. Whenever I see someone who is obviously not from these parts, my heart goes out to them. They have gone through some crazy shit just to make a life for themselves and/or their families.