This is kind of neat trick. Obvious in retrospect, but I’d never thought of it.
Any sort of cell formatting you can do can be saved as a style and applied elsewhere.
Why is this useful? Because often you want to protect most of your sheet from downstream users, while leaving open a few select spots for them to edit. If such editable cells share a style, you can turn them on and off as a group, or add new cells to that list by simply assigning a style to them.