Old war story time: in 1984 and 1985, when I was stationed in Korea, it was legal for soldiers to hire prostitutes because prostitution was completely legal in Korea. (There was even an office in the Ministry of Health to deal with prostitutes.) Every so often, one of them would ask me, "GI Joe you buy me drinkie?" I would tell them no but "when Joe comes in, I'll be sure to send him to you." They didn't like that very much.
But apparently the doll was Joseph someone-or-other until he enlisted, and then he became GI Joe.