They are coming to the US in droves precisely becuase the will be free to earn good wages...

Once here, they are earning so much US$, that they can send money home (probably to finance their relatives own immigration to the US).

They are hard workers. They do a great job. They want to EARN a better life. It's not their fault they can't Earn a good living in their own homeland.

Maybe someday, Mexico will turn away from Corrupt Socialism and adopt a fair and honest Capitalist model. Then the complainers in the US will be upset because the workers and factories flow into Mexico.

Note: Slaves are taken against their free-will. Also, many immigrent workers in the US are Canadian and European as well. If you really want to complain, complain about them.