I don’t know where you are but rear fogs aren’t illegal in the rain here and from experience they are nothing but helpful in heavy rain and white out snow. I am always so so sooo glad when someone in front of me is using them when it’s absolutely pouring. You really have to not be paying attention not to notice that it’s two lights and not three and somehow mistake them for stop lights.

In fact, Transport Canada recommends using them in fog, rain, or snow.

Use only if driving in fog, rain or snow as these lights can be confused with stop lights, distracting other drivers.

https://tc.canada.ca/en/road-transportation/safety-standards-vehicles-tires-child-car-seats/using-your-vehicle-lights-see-be-seen