Here I thought illegal immigration was a net gain for the American economy.
From the perspective of an employer the short-term gain of paying less for labor is attractive and a positive. For Americans who might be competing with "homeless Mexicans" it is likely a negative. And beyond these two simple perspectives lay more complex calculations of benefits and detriments.
Measuring the negatives against the positives requires far more data than a single anecdotal post about "homeless Mexicans." At least for me.