I've encountered this multiple times in different runs. When encountering the last trader camp before the border, the car I was using will suddenly disappear despite not being destroyed/abandoned and I am not able to take advantage of the weapon barter trader to make a little bit of extra food to maybe use in the camp or just for the last day. I don't know if this is a bug/glitch but it doesn't happen every time and most of the time we pull up the last trader camp no problems.