You don't. Without it, any app asking for root will get it. With a superuser app, Superuser, SuperSU (my preference) or any other similar app, you will be asked if the app should be given root. That, and SuperSU's ability to almost completely remove all signs that the device has been rooted, are about the only reasons to run any superuser app. (Running withoiut one is risky, because any virus or Trojan can achieve root and do anything [including deleting Android, Linux, the recovery partition, the download partition, all partitioning information, etc.)