While cheap hobby CNC mills and routers are great machines that allow you to build things a 3D printer just can’t handle, they do have their limitations. They’re usually powered by a Dremel or ...
In the world of hobby-level CNC cost and simplicity are usually the name of the game. Using inexpensive and easily found materials makes a big difference in the feasibility of a project.
CNC milling (rather than consumer-level 3D printing) is really the ideal process for almost all of these projects. I also have needs for parts I wouldn't brother with 3D printing, like hobbyist ...