The first set were his passage.
Even a guy fresh off the boat would get his shoes shined.
The pamphlet includes this poem:
Engineer and Salesman!
Steamships and express trains!
But above my eyes
stretch gigantic bridges
and the smoke of the hundred derricks
From "Song of the Gold Diggers"
George Grosz, 1917
Double Decker, 1932
And the final photo in the booklet, "Young American", is a strong connection to his great caricature and portrait work.