Your numbers are wrong. Here's the actual values for each of those images uncompressed:

    debian	101M
    alpine	4.1M
    amazonlinux	160M

These were determined with the following:

    for image in debian:latest alpine:latest amazonlinux:latest; do
        docker pull $image
        size=$(docker save $image | wc -c)
        echo "\n$image is $(echo $size | numfmt --to=iec)\n"
    done

Please note that it's important to only do this test with either a completely clean image store OR to save an exact sha256 image digest tag.

If you try to do a `docker save` on a store where you have multiple copies of an image, it's easy to mess up and save old layers too. I suspect that's what happened with your amazonlinux test above.