I agree with Bob in both his posts and understand the confusion, bollinger.
If you use the sync option on your Mac or on an iDevice, it goes to and via iCloud to those other Devices that have the same options setup to sync.
If your Mac is the ONLY device you own, or the only device from which you have permitted syncing, then those apps you've chosen to sync go to iCloud and stay there. In that sense only, they represent a backup.
But, of course, everyone should have a Backup (BU) strategy that employs Time Machine and/or a cloning app because these are "true" BUs in the sense that your Mac's entire content is backed up.
Hope that is a little clearer?
@bollinger, you asked:
From what I've said above, you will understand that to sync apps between devices necessarily means that those apps not only go via iCloud but are kept in iCloud - they can, in fact, be viewed by signing into
https://www.icloud.com via your web browser
Ian