This is less about cost of bandwidth and more costs of having edge POPs around the world.
With cloudfront (or any other edge cache system), you get TCP termination closer to end-users so the site loads faster, particularly if you have users around the world. Dropbox case study: https://blogs.dropbox.com/tech/2017/06/evolution-of-dropboxs...
Edge cache bandwidth costs quite a bit more than the not quite bottom of barrel IP transit that HE.net is selling.
With cloudfront (or any other edge cache system), you get TCP termination closer to end-users so the site loads faster, particularly if you have users around the world. Dropbox case study: https://blogs.dropbox.com/tech/2017/06/evolution-of-dropboxs...
Edge cache bandwidth costs quite a bit more than the not quite bottom of barrel IP transit that HE.net is selling.