I imagine it is thought that a light is unnecessary because you can see that the fog lights are on. It would be a useful reminder when they are on illegally. I apologise in advance if my post causes offence as I don't want to be pilloried again. Edited by: Beevee
If they are deemed as driving lights, not fog lights then there is no requirement for a dash light. At least that used to be the case (and got me off 3pts with a local bobby when I showed him the manual and lack of bulb on a previous car).