You are certainly correct about the inefficiencies of a traditional fireplace, and this would be very significant living in Canada.

But some of us reside in sunnier climes, like southern California. In thirty years in So Cal, I have never seen frost in my town and on only one occasion on an outlying island. So we can dedicate fireplaces to their highest and best uses, toasting marshmallows and raising morale. They are pretty good at chasing the chill away.