Exactly, different use cases. I have a list of meme-posting accounts that I don't want cluttering up my main feed. Same with SW. I think all that goes back to when I used TweetDeck (before it got bought up by the bird app), and used to have at least 4 or 5 columns of different interests - like one just for Nascar news and commentary, as I was a fan at the time. Lists and feeds come pretty naturally to me, but they wouldn't come as naturally to someone used to a single timeline of everything.
I created a mute list today, with my blocked accounts from Onyx on it, since I don't think they save anywhere else. Some other client created that list for me, but I deleted it. Now I added it back. Nice to have a record for when I switch clients, or when clients start using lists to handle muting/blocking.
Also created relay lists of my paid and free relays. Just playing with Highlighter.com, and making sure I have my current state saved pretty well.
Feel free to drop my npub in a client that supports lists. Nothing to hide (that isn't hidden and encrypted by my nsec).