What is the point of these ons in the chevorlet equinok?

Hi, I have a brocheure for an 2007 chevorlet equinok. in the Brochure they show the back seats. The back door seam to have to lock on on them. for example in the front of all cars they have the lock on on both penger and driver to lock all the door and to unlock them. I just want to know why they would put them in the back seat for kids to play with?? Can anyone tell me why that on is there??