Hello, I'm the developer of Lean. Live Photos come with a .JPG file and a .MOV file. Lean helps you remove the .MOV part. cynics was comparing the exact same thing above, because it's all JPG. When you use Image Capture.app, you'll see there is 2 parts with similar name (e.g. IMG_0000.JPG and IMG_0000.MOV). The amount reported is the size of .MOV file.
Side note: We helped our users save ~340 GB of storage since launch 
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