>'The real issue is after exporting them they probably don't send all that much money back home.'
It's my understanding that this is not the case. That remittance from the US is a pretty significant part of many developing economies [1][2].
I've yet to a met an immigrant professional in the US who didn't send huge amounts back home along with itent or at least hope of retiring there.
1: http://www.havanatimes.org/?p=94444 2: http://www.bloomberg.com/news/2013-12-17/global-immigrants-s...