most 'fog lights' on cars now are actually what used to be driving lights, use them with / without, full beams on little country lanes to throw a bit more light at the edges of the road to help you find your way.
They are different in that a fog light spreads a very wide beam around in all directions. Driving lights teded to be more concentrated on the road ahead.
The difference on the car is that a driving light would go off when you went onto dipped beam whereas a fog light stays on all the time.
Neither light is "dipped" as in they both shine lights directly at an oncoming driver (usually me). The driving light will dazzle oncoming drivers just like a main beam.
Fog lights are designed only to be used where visibility is reduced by fog so that the fog stops the light dazzling the oncoming driver. If you use a fog light when there is no fog you will dazzle the oncoming driver.
I am often dazzled by oncoming fog/driving lights. The big issue I then have is that I am less able to see cyclists and peds who may be in the road.
I feel it is my duty to discourage such dangerous driving so feel the only way I can do this is to put on my main beams (where it is safe an will not dazzle other drivers). If we all do this they will get the message. If I do it alone they get annoyed and put on their main beam. (there is a good point where you can get your beam on before they have time to react back). If we all do it they will get the message and perhaps notice they are dazzling me.
So for the sake of us cyclists I hope you all do the same!