In your own app it's easier than that since you already know what kind you want to get back from relays.
If you're going to be loading kind 3000x lists then the kind would be helpful because you'd want to have a way to go through the user's lists and only show the ones that are related to the game rather than mute lists for instance.
This came up in a NIP PR a month or so ago about emoji lists. There was some discussion about whether it's better to create new list kinds for specific types of items. Right now we have 30000 and 30001 which are supposed to be for people and "bookmarks" respectively but, in reality, people often mix kinds of things that they put into lists.