The Atlatl was the first tool that took advantage of physics on a grand scale. Take a spear, put it in the Atlatl and now you can throw that spear with 4X the force of just throwing the spear.

These made taking down large animals a lot easier. One spear with 4x the force is a lot better than 4 spears with no force modifier. Nothing in D&D offers a 4X damage modifier. This tool was literally better than magic.

If you are going to use one please use a hardened tip on your spear because otherwise it's probably going to shatter when it hits something. The easy way to do that is just burn the tip of your spear in your fire and then shape a new point on it. It makes a dramatic difference in the durability of that point.