The Virginia type of peanuts is what's sold at these events, as mentioned in a song written in 1908
... Of course, we sing the 'Peanut and Olive Song' on these occasions, 
and... [DOC] [TLE] Take Me Out to the Ball Game by Jack Norworth - Baseball Almanac [PAR] In 1858, the first known baseball song was written, "The Base Ball Polka!