Why do the daytime running lights not operate at the rear? The number of cars I have seen over the winter period with poor visibility conditions that are being driven with only the front daytime light on. These are easily seen from the front but are hard to spot when following from behind.

I assume these drivers think that a light is on at the rear of the car thus negating the need for dipped light. Would it not make sense for manufactures to fit a low level light at the rear that switches off when the dipped light are turned on. In my view this would reduce the risk of a rear end shunt in poor weather.