In the first clip, the guy jumping out of the way is a marshall-he starts blowing his whistle soon thereafter. In the fourth, it's a photog, and I think I saw his press pass flapping as he jumped out of the way (although I do not know if he was suppose to be in that location or not).
Most rallies have designated "safe" areas for spectators to watch. The problem is, these events are usually in the forests somewhere, so there's a large amount of area to police. Most of the fans know the dangers of standing on the edge of the road during an event, but its a risk they're willing to take.
-Wm.