Time machine volume does not have Backups.backupdb folder

When I created and installed two new Time Machine volumes, everything seemed to go well: the OS accepted the external disks, Add or Remove Backup Disk (in Time Machine system preferences) accepted them, and the backups all seemed to work as normal. Except for one thing...

When I examine the disks in Finder, there is no Backups.backupdb folder on the volume. There are a series of individual backup files of Kind Time Machine Backup (from Finder Get Info).

First question: why didn't a Backups.backupdb folder get created when I added the external disk? Does the OS no longer require that folder to function correctly?

Second question: If I need to restore my hard drive from one of these Time Machine external drives, will it work correctly without that Backups.backupdb folder?

Third question: If I want to clone one of these Time Machine external drives, the procedure is normally stated to drag the Backups.backupdb folder from the existing drive to the new, blank one. What should I do if there is no Backups.backupdb folder? Can I simply select all the individual backup files and drag them to the new blank drive and let Finder do the rest?

Thank you, in advance, for any help you can provide...