Same reason Rust people use a package manager made in Rust, JS people use a package manager made in JS and Java people use a package manager made in Java, becau

Same reason Rust people use a package manager made in Rust, JS people use a package manager made in JS and Java people use a package manager made in Java, because it's close to the context you're already in and if you need to extend/modify/remove something for your own use/for the community, you already know how to do it. I myself would never use Hyper, but I can see why people would. If there was a comfortable terminal in/for/with Clojure, I'd at least try it.