It's a selection bias issue. The categories you have listed are essentially web services wrapped in an app shell. Of course they need the internet. Consider these examples:

- Photo/Video editors - Snapsheed, Lightroom, Video trimmers etc.

- Document readers & scanners - PDF viewers, e-readers, OCR scanners

- Note taking - Obsidian

- File/Password managers - Authenticators etc.

- Single player games - Chess, puzzles etc.

- Audio/Video players - VLC players

We've just become conditioned to accept that every app needs to phone home for tracking and ad-delivery.