We have an issue of kangaroos creeping close to the edge of the road to eat the grass that gets extra water from the run-off from the road. They especially like to come into road cuttings where there is a ditch, which has the lushest grass and may even have water to drink.
Then a car comes and the roo panics. Roo panic behaviour is to bound along at full speed, keeping generally to open spaces, and make sudden swerves. Swerving is especially likely if The Danger is very close.
This works well with things like dingoes, but very badly when the open area is the road and swerving means you jump right in front of the car. In road cuttings this is almost inevitable because there is nowhere else to go.
Now remember that roos are nocturnal and this happens at night, so the driver can't see the roo until it is in the headlights, and then the roo is dazzled and can't see at all.
Driving lights and roo bars are popular car accessories in country Australia.