In PT you have playlists while in Nuendo you have track versions, lanes and parts and events on top of each others that can each be used to play different audio.
I guess they are here for historical reasons and not to break compatibility (which is a good thing!) but I see how the slightliy different concepts can mix up new users.
If there is one thing that really annoys me it is that you cannot expand audio that you have put on top of each others to lanes while this is possible with audio that you have recorded on top of each other. It would be one of those tiny things that would be a huge step for alternative take manament of location audio.