Why is there a demand for Bunk Beds & spiral staircases

Like other folks have said, bunk beds and spiral stairs free up more space in a house. I’ve never had the packs that included bunk beds in the sims, but I do miss spiral stairs (and ladders).

If I recall, spiral stairs weren’t added to Tiny Living because it was a stuff pack. New build mode stuff/mechanics aren’t apparently added to stuff packs (like, a new wallpaper might be okay, but not a whole new thing that changes build mode). I think one of the gurus said it wasn’t just budget, it was also game mechanics.