If you are backing up online and you think you are backing up the most important part of the computer (SQL), then you know that. Why would you not want to back up SQL?
Sure, it's great to back up most of your computer files. And, yes, you are set with the .enc file. But, you are not OK with SQL with most online backups.
Most enterprise versions such as with Carbonite are $599 a year and allow server backups but not SQL or Exchange for that matter.
