New Orleans is a port city. It is located on the Gulf of Mexico. There is also a huge lake, Lake Pontchatrain, and, of course, the Mississippi River which empties into the Gulf. With all this water, there have always been the shipping and fishing industries. In fact, during World War II, there was a great deal of ship building and ship fabrication, and many construction facilities were established along inland waterways of the Mississippi. In 1947 the war was over, but there would still be some steamboats as there are even some today. The shrimping business was huge, as was harvesting oysters. In addition, cotton and other products were still sent out from the Port of New Orleans. The Maginnis Cotton Mill was constructed in 1882 and still producing cotton products until the mid-1980s. There were iron mills and steel mills, as well, providing materials for ship building and other enterprises. Of course, New Orleans has always been known for its great food, so there were many restaurants and hotels where people were employed, as well. With many wealthy residents, there were many financial institutions. These wealthy people employed household help, gardeners, and even chauffeurs. Dressmakers, hair stylists, and merchants of all kinds were also prevalent. Public transportation would also employ many people, as well (streetcars, buses, trains, etc.).
In A Streetcar Named Desire, the play, Stanley Kawolski is a factory parts salesman, but in the film version he is merely an employee in a factory.