I've read somewhere that the poor would snatch lumps of coal from the train tracks where they would fall off of the over-laden lories. And yes, Jack (& the rest of the underclass) would have been much more used to lower lighting conditions than are the modern-day population even consider "annoying". There was no SERIOUS Light Pollution crisis in the 1880s!
Regarding starting a fire- well, from Boy Scout training, to start a fire you need tinder to start the spark, kindling to get it hot enough to actually burn and then the fuel to get the long-duration heating fire. Coal is the fuel and it is darn-near IMPOSSIBLE (at least very difficult & time-consuming) to START the fire directly from the spark using fuel only. (One reason that the match was such a useful invention.) These people usually had embers already burning or material that they had scrounged to start the fire set up in the fireplace.