Favorite Formats can be specified in commands to change the format, so it may have been used to display a list for selection (although there are built-in commands for that).
Path formats can't be given to commands though. What would your use-case for listing those be?
The usecase would be a rewrite of my old and no longer working DOCleaner using only the Opus APIs -- as opposed to XML config parsing which was necessary before the APIs for querying the Favorites and Folder Aliases (and possibly the Tab Groups, have to see how usable it will be) were introduced.
I have trouble with missing APIs for both the Path Formats and Path Labels (file or folder color assignments) which I've mentioned before, but would really like if we could have a full set of APIs for querying this stuff (as you could see in the old DOCleaner, the hacky XML config-parsing breaks easily over time).