What’s more it might actually save people’s lives and preserve property. In their 2006-2007 Fire Stats the New South Wales Fire Brigade (in Australia) states that in 98 out of 483 recorded residential fires for the period the ignition factor was falling asleep. Presumably if you have a lit cigarette in your hand and you fall asleep, one possibility is that if the cigarette falls somewhere where it can ignite other materials and smolder, it is likely to eventually spread beyond that point of ignition.
Now imagine if the cigarette did not keep burning. I presume there is a strong correlation between the cigarette not continuing to burn and a reduction in the risk of ignition in the scenario described above? This is further reinforced by the statistic that a further 21 of those fires were attributed to alcohol. Again, with a possible connection to smoldering cigarettes as an ignition source.