"Chubba, how dare you! Take that back right now! Grrrrrr!"
Hush, child. Allow me to explain. 👽
Basically, these two can't do shit without Freddy or Foxy.
Why is that? Simple.
Unlike Freddy and Foxy, Bonnie and Chica can only attack the player when the cameras' tablet goes up and down.
But if you never check the cameras in the first place, you cannot be jumpscared by them.
So, if both Freddy and Foxy are inactive, you can just sit on your ass and patiently wait for your nightshift to end.