A bicycle is defined in the Road Traffic Act as a pedal cycle and is defined as a vehicle under the act and are governed by the act. So bicycles have to obey all the regulations of the act - the primary one being "keep left". So as a vehicle, bicycles must act as a vehicle. Riding contraflow is an offense just as driving a motor vehicle contraflow is. Runners are not allowed on public roads. They are expected to keep to the pavements like all pedestrians, so the direction of their travel is not determined by the act. However, many runners break the law by running on a public road, which is in itself and offense (it's called "jaywalking"), but the direction in which they break the law is of no consequence. Since they are not a vehicle, they are not expected to keep left. I suppose the reason many runners run into oncoming traffic is that they want to see the car that hits them. And if you think cyclists are stupid on the road, runners often are a lot worse. Disclaimer: I am a cyclist and think cyclists who ride into oncoming traffic are morons. I also run and think that runners who hog the road as if it belongs to them are also morons.
