Maybe this is a "blind spot" of sorts to the developers of Tree Sitter, but I find that the CLI is directly useful for end users to perform queries on their code. Maybe it would be better if we had dedicated tools that were more oriented at end users rather than developers of TS grammars, but it seems silly not to use a perfectly good tool that already exists.
Somewhat of an aside about building grammars, I have found that the grammars are relatively hard to make small modifications or extensions to. Whereas it's relatively easy with e.g. traditional Vim syntax highlighting. Making grammars easier to extend would be valuable for users of languages like SQL that have a zillion custom dialects.