being able to restore individual files / folders should be basic functionality.
being able to restore the database with a different name, restore the entire website file set to a different folder, or restore the entire website backup to a different domain / subdomain / staging should also be possible.
i can see where needing to do any one of these can be a regular requirement.
when needing to restore a backup, or part of a backup, it's not always the case that we want it to be restored back to it's original location, often we want the exact opposite, we want the original live website to remain undisturbed.