It seems no one is replying here anywhere?
I have the same issue as you: While Jason wrote in the s2m help "it costs only a few cent to use s3/CF combination, and so we did, I am seeing that we are now being "ripped off" with huge charges.
Enquired of amazon, they replied "It's that much traffic"
LOL, I wish! Looks like Cloudfront has a bug that "bots" can "view" videos and "listen to" audios!
So now we too NEED TO get rid of that cloudfront "service",,,