As someone has already mentions this is completely situational, it depends on traffic, if traffic is running smoothly none, its there place to wait for a space to move out of the junction.
if i'm stuck in traffic and the queue passes a junction i'll most likely let out one car that is going in the same direction as me and, let out anyone crossing my lane to go in the other direction.
as i do for merging lanes, i'll personally allow space for one car to merge in front going on the assumption that the car behind will leave space for one and so on, seems fair to me keeps everything rolling smoothly.