Another positive benefit of the Green Book was that it was essentially an early niche business directory. Ironically, some of the greatest economic progress for Black Americans occurred during the oppressive Jim Crow era because Black consumers had to buy goods and services from Black-friendly and Black-owned & operated businesses.
Probably the best example of this was the Black Wall Street in Tulsa, Oklahoma ( https://en.wikipedia.org/wiki/Greenwood,_Tulsa#The_Black_Wal... ), which was the wealthiest Black community in America at the time (and subsequently the site of the worst race riot of the 20th century).
Resources like the Green Book benefited Black businesses as well as Black travelers and consumers.