As a followup on real world use cases, I am currently working on a Drupal project, where a color palette has been defined. We need to be able to both create a dashed border, and/or a background color for various content, and styling only fx. blocks is not sufficient.
This can be exemplified by the following: We have a bunch of custom blocks, which we want to wrap in a dashed border. If we add the dashed border to individual blocks, each of the blocks will be wrapped, which is not the intention, so we need to be able to give the section containing the blocks the dashed border styling.