Any way to avoid local copies of Snapshot archives?

There are local backups being stored on my local server in addition to the backups being sent to Amazon S3.

Is there any way to avoid keeping one local copy? The whole point of making a backup is not to have backups ON the production server but it doesn't look like there is a way to avoid this. If I set to 0 for local archives then it keeps copies of all backups. WHY??

I just want to make backups on Amazon S3 and not on my local server. It's getting clogged!