It's for people who don't have root access to a remote terminal (super computer users, generally) but want more up to date packages.
Some packages (my favorite example is youtube-dl) are useless if they're not up-to-date. And sometimes the new version has a feature that's really important to you.
I'm using it for ripgrep and node, for instance. ripgrep isn't available in apt, and the node version in apt is incredibly outdated.
There's a reason most software these days tells you to curl an installer and pipe it to bash, and that's because distro package managers never have the latest version.
Here's ripgrep's apt installation instructions:
curl -LO https://github.com/BurntSushi/ripgrep/releases/download/0.10.0/ripgrep_0.10.0_amd64.deb
sudo dpkg -i ripgrep_0.10.0_amd64.deb
Linuxbrew is just so much easier:
brew install ripgrepIn case you're suggesting Linuxbrew is unnecessary (I don't think you are, but just in case), there's definitely something way more convenient about just using Linuxbrew to install everything, than to track down what software is best installed from what repository.
Gentoo, Red Hat, Fedora, Ubuntu, Debian, Mandrake
So I've had plenty of exposure to three major package management systems and a bunch of distro-managed repos, from the perspective of a desktop user (I've used Linux on the server plenty, too, but that's less directly relevant). I've poked around in a few others in a desktop context—Slackware, Arch, Nix, probably more that I'm forgetting.
I also used Macports for over a year.
Homebrew's the most pleasant overall solution for managing user-facing desktop software that I've used, by a long shot.
I used to manually compile things like Node.js and ripgrep from source to get up-to-date versions, but these days I just use Linuxbrew.
I am using Arch - seems pretty up to date:
[gerdesj@jglaptop ~]$ aurman -Ss ripgrep
community/ripgrep 0.10.0-2
A search tool that combines the usability of ag with the raw speed of grep