Actually I use them a lot, on single track roads in the UK, they provide a MUCH better coverage around the front/side of the car -- I don't know how many critter I managed to dodge because I saw their eyes in the hedges.
And it doesn't really matter how regularly. If you are driving in those conditions… you only have to crash once.
In the UK, it's not legal to have the fog lights on unless your visibility is less than 100 metres in front of you. That's basically the same range as your dipped lights have, and less than five seconds worth of visbility if you're doing 80 km/h.
If your visibility is reduced so much, your best bet against crashing isn't just to scatter some light near the bottom of your front bumper, but to engage the rear fog lights and drop your speed significantly.
On rare occasions I've had to drive in conditions so bad that the front fogs on my car were providing the main or perhaps only useful illumination of the road immediately ahead. We were all just crawling along at barely more than walking pace, even on roads that might normally have been major high-speed routes. Vehicles without appropriate lights were parking up, totally unable to make progress until the weather improved. That definitely hasn't been an annual occurrence in my experience, but it's happened to me more than once.
I'd be very wary of buying any new car without excellent lights today. I'd even say the lighting would be in my top 5 deciding factors. Basic headlights have improved dramatically in recent years, thanks to better light sources and adaptive technologies that offer better coverage without dazzling other road users, but the specialised lights like high visibility and reversing lights are also important at the those times when you do need them.