Kerosene and gasoline were available in small quantities through hardware merchants, grocers, feed stores, and the like—and that sufficed when autos were owned by wealthy hobbyists. But widespread auto use dramatically changed the picture. Gasoline consumption was 25 percent of the petroleum market in 1909—and 85 percent a decade later. Specialized pumps quickly came to be preferred for safety, and specialized marketers with specialized retail outlets followed quickly. The demand for gasoline spurred the invention of cracking technology, so that crude oil would yield more gasoline and less asphalt and other heavy products.

There's a little about this in John Jakle and Keith Sculle's 1994 book The Gas Station in America, p. 50.