None of us have a clue but it's still fun to speculate. Some if it might even turn out to be correct.
I have to think they will sort of follow the food truck model. Announce on twitter they will be here, here and here at these times. They are not making money while driving around and since they will need to sort of keep to a schedule flagging them down for a burger mid lake seems unlikely; they would never get where they are going otherwise.