Terrifyingly simply, actually. What it is is a matter of surface area; the charcoal, a round, dense, hard object, is more difficult to set fire to than what can normally be found as kindling in the woods. Even with the newspaper, the lighter material with the greater surface area being easier to catch than the charcoal, and the lighter fluid, whose fumes are the only thing that ignites- you don't set the fuel itself on fire, just burn off the vapors, the charcoal itself still needs to get to the correct temperature alter its physical state, allowing for a change in texture, surface area, and chemical composition, making it much more difficult to light, whereas the leaves, twigs, and stray bark in the woods IS the lighter material with the greater surface area, catching easier for a larger ground fire that eventually sets the woods as a whole on fire.
With the one you only need a spark, and with the other you need a whole lot more.
With the one you only need a spark, and with the other you need a whole lot more.