@Tim P Dave is correct, connecting to SQLite with Xojo creates the extra files whether you like it or not. I have had an app rejected from the MAS because I forgot about this. It's not hard to work around. Copy the sqlite database out of the app to either app support or temporary to open it.
I will test it then ...
From what I've read of the Sqlite docs, I was under the impression that it only created the extra file if you used WAL... but of course Xojo inc could change that in its plugin which is why I asked...
If the plugin's behavior in that respect is different from that of SQLite itself, that should be documented in the language reference,
In any case if it's not needed by SQLite, Xojo's plugin should avoid doing it if possible.
BTW for DB's I'm going to write to (most cases), I do as you suggest... But I did not see the point of doing that for a read-only DB, as it is conceptually no different form any other resource