In another profession entirely, I think of Jimmy Stewart. He was already a pilot, so after Pearl Harbor he went directly to the Army Air Corps. You're too skinny, they told him. Stewart went home and started to binge. Fattened up, he was accepted and served on bomber missions in Europe, becoming the commander of his squadron, and earning the Ditinguished Flying Cross twice.
Clark Gable, at the time possibly the most famous man in the country whose name was not abbreviated "FDR," also volunteered, signing up as a private. They tried to stick him with making films about Air Corps pilots, but he insisted on flying combat missions. He also won the Distinguished Flying Cross.
Tyrone Power flew transport missions for the Marines, including missions into and out of hot spots like Okinawa and Iwo Jima.
In sports, to name just two others, Yogi Berra was at Normandy as a gunner's mate and Ted Williams famously missed three prime seasons to serve during World War 2 and was called back to fly combat missions in Korea.
I think it takes nothing away from Tillman to note that, at another time in our history, he would have had some company at the recruiter's office.