He met Harry S. Truman at the age of 13 after being invited to the White House to be honored for his bond sales.
Grainger also met John F. Kennedy shortly before his assassination as an editor of The Valley Voice, having been invited for a luncheon to discuss resolving racial problems in the South.
Four days later, Grainger was asked to help coordinate Kennedy's visit to Muscle Shoals in celebration of the 30th anniversary of the Tennessee Valley Authority.
Grainger wrote a memoir titled My Journey Through a Changing South, detailing his childhood in rural Alabama during the Great Depression.
In his memoir, Grainger claimed to have experienced several near-death experiences throughout his life, including nearly dying twice as an infant, almost drowning as a teenager, and escaping death as a young adult while flying on a small plane.