They are also passengers on a kind for truck-bus peculia to SEA called a songthaew (Songthaew - Wikipedia, the free encyclopedia)
Those people were standing on the back step of this little truck-bus that had a flat on the road from one small town in central Myanmar to another. All of the people you see here were on that one vehicle - together.
Here is another passenger.
this is a different leg of that journey after I had gotten off as an example of how packed they get. They are good places to inspect the next person in some detail.