I usually put it in too. You would be correct if the defaults were always set like we expect them to be. But that isn't always the case. The defaults are whatever whoever put the distro together decided they were. It doesn't hurt to have it and it might prevent an additional problem from popping up.
Insanity: Doing the same thing over and over and each time expecting a different result.
Democracy is 2 wolves and a lamb voting on the menu. Liberty is an armed lamb protesting the electoral outcome. A Republic negates the need for an armed protest.