This is how all DAWs operate. They reference the audio tracks that were brought into the session and apply any manipulation to the track by referencing the track image and applying the changes without being destructive to the original audio. If you are in your session and go to the main menu, select File and then " Save to New Folder "; Studio One will collect copies of all the audio being used by the session into this new folder. Then, you will be able to see the information and data sizes you had expected to see.
** this is also a good practice, to allow you to fully back up your sessions and or be able to transfer the entire session collectively over to another computer.