According to steinbeck, how does the service that migrant workers provide compare with how migrant workers are often viewed in america?

The service that migrant workers (or "New Gypsies") provide is absolutely essential to supporting the economy of America, specifically for the industry of agriculture as the population of migrant workers who move from place to place to harvest crops is expendable, cheap, and in constant supply. This allows farmers to make real cash profits on their crops, to expand, and to feed a nation of consumers as well as provide for a foreign market. Migrant workers are literally the backbone of agrarian culture, and, yet, they are treated as absolute pariah. 
Migrant workers are willing to work for almost nothing as it is more than they would earn in their own countries, and are seen by Americans as lower-class as a result. It goes against the "nature" of American culture, which is to earn as much as possible based on a capitalist view, to be willing to do so much labor for so little money is looked upon with disdain. Further, migrant workers are often not citizens, and so they are treated harshly for utilizing services provided by the American government when they are not owed to them, in the eyes of the American people. They bring with them entire families who need to be cared for and fed, which is frowned upon as they always seem to be homeless or hungry. 
It is obvious that Steinbeck's view is that these "New Gypsies" deserve much more respect due the immense amount of work that they do and because they are a cornerstone of American success ans stability, but that Americans will never accept this group of people. We are meant to consider this discrepancy.