Only if you take the short view. You fail to factor in their pressure on the welfare systems, health care, education and the fact that they send most of their income back to Mexico via Western Union and MoneyGram.
Not to mention uninsured/unlicensed drivers running up big bucks in damage & fatalities on the highway. The list goes on and on.
These aren't exactly hidden costs.....and you're saying that we are getting as good deal?