Huge macOs 10.14 System Folder Size Difference Between Finder and About This Mac/Storage

I am puzzled by the discrepancy between the amount of space left on my system drive and the space taken by each folder as displayed by the Finder.

Let me explain: my system disk is a 480 GB SSD (479.89 GB to be exact.) Under Finder it shows 130.39 GB available. If I add all the content sizes (Users Folder size + Application Folder Size + Library, etc.) it all adds up to 242.61 GB.

242.61 GB minus 480 GB, I should have 237.39 GB of space left and available. But I only have 130.39 GB. That's 107 GB of space missing. What the heck?

Examining the About this Mac/ Storage shows an even more puzzling story:

Here the System takes a whooping 173.5 GB of space!! On the Finder screenshot above, the System folder is a meager 10.12 GB. That's a 163 GB difference!! What gives Apple???

I searched the internet for an answer, and stumbled upon this post: https://discussions.apple.com/thread/8084507

In there a reader suggested to look for Time Machine local snapshots - invisible files that can take a lot of space on the system drive. Only.... I do not use Time Machine. Nethertheless I was curious, maybe I turned it on at some point and forgot about it, I wanted to be sure and entered the command "sudo tmutil listlocalsnapshots /" in Terminal. And I got this result:

Ah ah! I do have local snapshots, only they are not generated by Time Machine but by Carbon Copy Cloner, a (great) Bombich software.

Lo and behold, there is such a feature in the software since the introduction of macOs High Sierra and APFS- formatted volumes, and in my case... snapshots is turned on! Ah ah! We're getting somewhere.

Snapshots in CCC Preferences, is enabled.

And looking at my system drive in CCC I can indeed see the nine snapshots, with one that's 39 GB. All right, that's a start. But it's only a portion of the 107 GB not accounted for.

Hmmm. Since these snapshots are old from last year, at this point I will experiment and just delete them to see what happen. I should get back at least 39 GB, then we'll see where the rest is hiding.

So I selected the snapshots and deleted them all. CCC went on a re-reading of the volume and...

 Bingo! I now have 246 GB of free space! CCC snapshots were taking all these 107 GB of unavailable space, much more than the apparent 39 GB something.

Back to normal!

All right, so if you do have a discrepancy between the available space on your system drive and the space occupied by the system and your user files, chances are snapshots have been created by Time Machine, Carbon Copy Cloner, or another backup app.

You might want to keep them, or you might want to delete them to free the space for other files. I wish Apple would list them properly in the About this Mac/ Storage as SNAPSHOTS! Is that too much to ask?