The anubis docs website is used as an example of how anubis works.
Also, if you are not using a big CDN (e.g. Cloudflare), you still need to pay for the traffic (even if you don't pay as much for the CPU). This is doubly true for smaller CDNs like Bunny.
Not only is it an example, it specifically is one of the first things I use to test experimental features so I get data back instantly.