As Tony said, if you drop a folder of songs from Explorer into the PLAYLISTS in Emplode, You will automatically create a playlist with the same structure in the PLAYLISTS.
If you drag a folder into any of the soup views in Emplode all of the directory structure is forgotten and only the songs are imported.
You can have songs on the player that dont appear in a playlist but you must use the search functions to select it.
In emplode you could create playlists of artists from listings in soup view, but you need to create the 'playlist container/folder' manually.

There is nothing stopping you from dumping everything into the soups view and only having a few select playlists. But remember that the soup views are only construced by the tags of the files. however once the track is imported the tags are written into a database and the tags themselves are not used again. I'm sure there's a FAQ on this!

If you had no playlists defined, you could only access your tracks from searches on the player. Playlists just add another method of accessing favourites.