@EternalSunshine Saying they contain a third of the Stuff Pack content is generous. The Fitness pack contains entirely clothes - and it doesn't exactly fill in any gaps - the furniture pack contains clutter and counters - clutter is never interacted with and many counters are reused meshes. Compare either of these packs to something like Paranormal, with clothes and gameplay and functional items and new animations, which all require new meshes and programming.
Plus, on average you'll get 60 new items, often more in a stuff pack. Between THREE Kit packs, you get 43 pieces.