Spotify Metadata

[Nutul]

(...) I wonder how one might go about going around the API and without having to directly rely on an account, a key and all that.

You can "curl" or "wget" the html page of Spotify for the track you want; and parse it: there are IDs in metadata tags that can be used to collect artist, album and album-art with subsequent loads.
I had a POC few (many...?) months ago. It may be slow, of course, compared to the Spotify API.