I've never seen the attraction of a turbo trainer. I'd rather go for a bike ride. We hardly ever get icy roads in the town.
I thought the same until I started to do some interval/hill training. It's much much easier to do on a turbo than out on the road.
When doing intervals you don't have to watch out for pedestrians/cars/cyclists/mud/rocks/potholes/deer/etc when doing 20 seconds at maximum effort.
Same for hill intervals and you can also make the perfect incline hill by adjusting the resistance. My nearest 18% hill is about an hours cycle away, same for the nearest 10% hill that's long enough to be useful.
It's also much easier in the dark.
(I don't have a turbo though but I just go down to the local gym and use one of their stationery bikes to do my intervals. I can then go for a nice relaxing swim too.)
I'd agree that using a turbo to "get the miles in" would be insanely dull. Winter miles / LSD (Long Slow Distance) is made enjoyable by seeing the world and being distracted by anything and everything.