The issue is not about working in this case, its about social, economic and racial class. Those of a certain class are given a free pass with very few strings attached, those of what is perceived to be of a poorer or 'lower' class of people are limited in there oppurtunity to come to America.
Let me explain, as I know the Carribean experience first hand and better than the European one I will use that. Cuba was the crown jewel of the Spanish empire, with every gold shipment passing through Havana with a vast govermental system set up and needed to run the empires New World gold mines, plantations, banking. etc.. The best schools, the most educated, some of the wealthiest families came from Spain, making Havana a very modern cosmopolitan city, with the original darker skin native indians being replaced by those of light skinned Spanish descent.
So when Cuban dicatato Castro came, the cubans were welcomed with open arms to America, we went and brought the children over in operation 'Pedro Pan', we passed laws so they could walk onto a beach on U.S. soil and have a instant free pass to american citizenship. We welcomed the hardworking, well educated, well to do social class of cubans that came.
But the island of Haiti only a few short stones throw beside cuba, with its own dictator 'Papa Doc' and son ravaged the poorer people there, we looked the other way. We sent coast guard cutters to keep them away from our shores, if they did manage to make the hundreds of miles across the dangerous waters we sent them back. So what made the difference.....