When it's 40 degrees and after bedtime, but you're out of toilet paper so you have to go to the grocery store and it's raining buckets outside (January weather in April!), that's when you know why they put those fakey, gassy smelling firelogs right next to the door at the grocery store. At this moment, they are impulse items - like magazines or candy bars or nail clippers. So you put down your bag of groceries, dig around in your wallet for another 3.5 dollars and take home the promise of 3.5 hours of warmth and light in a paper wrapper.
And it works, because driving home from the store, the clouds break and you see a little sliver of moon glinting through. And just that fast, the rain is over.