I spent the holidays with my mother in Los Angeles, who collects rare first-edition books. While I was visiting, she opened "The Complete Sherlock Holmes" (circa 1930) and an old San Francisco MUNI transfer fell out. We don't know whose it was, or how long it was in that book. We're not even certain how old this ticket is, but google tells us that John M. Woods was general manager of MUNI in 1972, so it's probably from that era.
Reading a rare, first-edition copy of Sherlock Holmes on the bus sounds like a very San Francisco thing to do -- no matter what decade.