Do you really think that most people heating with a non cat only heat 8 hours a day? There are many many of us heaing 24/7 with a non cat.
No, I think it's less. Most wood stoves and fireplaces sit cold all the time while lazy people use their furnaces. Don't fool yourself, the folks on this forum and even the ones calling a chimney sweep are the enthusiasts that use their stoves significantly more than average.