The very rear of a grab chara in KoF is that they can punish you on-the-spot with their grapples, and that it makes your approach much more difficult. Using simply B SAB eliminates much of that. Of course you still have the EX version, but you also need meter for that, and 2 meters + drive for the super cancel. The D SAB is simply free, can be combo'd into from close normals, and can punish rolls, and be done near instantly out of hop pressure. You can also cancel into it from Gattlings, if you so desire.
As far as C Gattling goes, it can be combo'd into off heavy normals (Great after a ranged Crouch C), and also has an extra hit on the ground, which makes it easier to cancel into a grapple. The DLD followup also grounds them again after the juggle, and sets them up for more wakeup mixups.
Just relying on B SAB weakens your game, overall. The move is punishable when spammed, it can be baited, and it overall loses effectiveness when you play aganist people who know KoF more. Alt guarding will destroy it, hop and jump moves will destroy it, spaced multi-hit moves that leave you in air during multiple hits will devour it, and leave you comboable... sure it's a great tool, but it's only at it's best, when it's mixed in with his other options.