Well first of all you underestimate the intimidation someone wielding a knife is.
Secondly, that is why I proposed the ranged skill, because your accuracy would be a major hindrance against incoming targets
Thirdly, It can be used as a way to SLOW DOWN enemies, not just kill them. When you throw a blade large enough, such as one on a 7 inch blade, it can lacerate a leg muscle, causing a zombie to fall to the ground, unable to use the leg anymore.