If I had to guess it's probably not the $5/month as much as that it's an incremental offsite backup service designed and marketed for ease of use and high avail

If I had to guess it's probably not the $5/month as much as that it's an incremental offsite backup service designed and marketed for ease of use and high availability... not an Amazon Glacier competitor. If you didn't plug a removable drive in for a month then this really isn't the market they're looking for. I could be wrong but it seems at least as likely as the suggestion that they're just out to get you somehow.