The Trading Commodities for Coffee ranks the second largest.
The most popular Coffee is the Arabica but also has a higher rate coffee called Robusta. This coffee is grown at a high altitude of over 3000′ ft., the plant is grows slower and because the elevation is higher the air is cooler and this allows the “complex sugars” to extend into the bean.
The main species of Coffee are Coffea Arabica and Coffea Robusta.
The Robusta is inexpensive, slow growing, and not very flavorful. It is also processed into Instant or Canned Coffee. Often Commercial-grade” roasters will use this type of Coffee to blend, to reduce costs and make more profit.
Some of those all night dinners serve their house blends and this is the cheaper coffee.
Reference: Coffee Cafe by Sherri Johns