well everyone has a different way of getting around not being able to see at night. as you can see in this thread, the common way is to throw sticky torches all over the place. people don't play the game in the dark in the early game, and since the prevailing way of getting around the darkness is pretty silly and immersion-breaking, i figure why not let players have a more realistic feeling way to do it.
the thing about this game is everyone sets their own difficulty. some people like very slow progression and will turn loot down and difficulty up. some people want a relaxed experience and will make it so zombies can only walk. and as i said earlier, people don't play in the dark, they throw torches everywhere. i figure, why not have the option to have a light source in the early game. people who don't like it don't have to use it, but there are players like me who will just turn the brightness up so they don't have to throw torches everywhere. maybe i'm in the minority on that, and if people don't have a problem with the way things are now, then we can just let it be. maybe i'll make a mod for myself like has been suggested.