"Long winters with heavy snow fall and icy road conditions. Sure, some folks drive them year round. But the number of rwd cars on the road when snow is on the ground is nearly zero."
Eh, I grew up driving an old caprice in the mountains of PA - no anti-lock, no traction control, not even posi-trac. My current truck is RWD only, although I don't live in the mountains anymore. While FWD can offer a slight advantage, I don't think it makes much of a difference as long as you have the proper tires and make smart choices.
So it is drivable.
I think it's more that the people who own the nicer trims of those cars try to save them from the salt or people who can't drive. Not to mention that RWD cars are already a minority of the vehicles on the road, except for 99% of the time the trucks you see will be in RWD.
Yeah, it's definitely more of a single person's car, or a second car for a family without small kids.