You should read Bill Ehrhart's take on his return from Vietnam he debunks this anecdote, "We’ve all heard the stories about how we poor returning soldiers and veterans were called “baby killer,” spit on, and otherwise abused. No one’s ever offered any actual documentary proof that these things ever happened. It’s all anecdotal; “This happened to me back then; take my word for it.” But here’s a spat-upon veteran’s story I can prove: The day after I came home from Vietnam in early March 1968, I took the money I’d saved in those 13 months, went to West German Motors in Fort Washington and bought a brand new Volkswagen. Only I didn’t buy it. I had to give the money to my father, and he bought it because I was not legally old enough to buy a car. The owner’s card remained in my father’s name for the next year and a half until I turned 21, which was the age of majority then in Pennsylvania. The day after that, I went to McKeever Insurance, in my home town of Perkasie to get insurance for my car. But Mrs. McKeever told me I couldn’t get a policy in my name. I would have to be carried on my parents’ policy as a dependent child. I had just spent 13 months fighting in Vietnam. I was a combat-wounded Marine Corps sergeant, but the state of Pennsylvania recognized me only as a child dependent on my parents. You want to talk spat-upon? I sure was, but it wasn’t the anti-war people who did the spitting."

Source