I can’t believe back then Americans were spitting on the soldiers. I couldn’t imagine doing that. Horrible. It wasn’t their fault
It never happened. It was an urban myth that grew up AFTER the troops came home. It was just a metaphor for the soldiers feeling disrespected. There was no such news at the time and nobody now plausibly says, "It happened to me." it's all, I heard, someone told me, I read.
It's obvious on the face of it no one would do that: what, to a fit soldier likely to punch out anyone spitting on him? Crazy thing to do and no one did it.
I have always seen that as an interesting way myths grow up --- as metaphors. Like the Obama born in Kenya one. I love that one, a total metaphor for "he doesn't belong here."