Carpenter pencils have advantages. The rectangular cross-section doesn't roll away. If you use it as a winder for string or fishing line the rectangular section winds up several times the length per wrap. The heavier wood section means if you use it for tinder you have more to work with. The heavy lead is tougher and less likely to break. If you know how to sharpen it, with a knife and into a flat knife edge, you get both fine and wide lines and the fine line lasts longer on rough materials. The wider cross-section is easier to grip if you are wearing gloves or your fingers are frozen while still laying flat in a shirt pocket.