There's many things Nier doesn't understand, about this world, her own world, or the towering thing in front of her, but she knows this: there's a fundamental gap between a living thing and a machine. It can't understand what it's like to be alive, because it never will be alive. They can't understand things like love, fear, or sadness, and even their pain is just a crude simulation of real emotion. Memories of the time her mind and body were replaced by that mechanical form courtesy of the Island Stars flit through Nier's mind; she knows these things are true. AM's display of anger, even that sickening facsimile of breathing, it's all just a show, an imitation crafted by some unknown creator. And the more it talks, the more she just wants to get rid of it.
"I know you don't like them," she says, frowning. "But you wouldn't really be able to appreciate them, even if you did. How they smell, how they feel, what they mean... I mean, you don't even understand chocolate."
She remembers the machine that called itself Nier wondering at the world around itself, marveling at how alive the city was. Touch sensors in its fingertips, chemoreceptors built into its head, audio receptors, visual light receivers, a suite of synthetic senses all built to emulate the real thing, and every one of them failing to understand what it meant to be alive. Perhaps she's merely meting her frustration out on AM, because it's probably not its fault it was built like this. But it's right in front of her, and that mechanical Nier is forever beyond her reach.
Nier can't help the sneer that touches her lips. "Were you built like this? Did they create you to throw tantrums in public? They must've hated you, too."
She knows that pain as well, the feeling of being rejected by the ones who brought you into the world. The NPCs in the grocery store have begun to give the two a wide berth as AM knocks more items to the floor and Nier winces. She doesn't like to draw attention to herself, she doesn't like to act out where others might see her, and she doesn't want to cause trouble, but this- this would be the opposite, in a way. This would be fixing someone else's mistake.
The tenseness in Nier's body melts away as she comes to a decision. She won't be spoken to like this by a machine. She'll do everyone a favor and dispose of it.
"I don't do those... Death, get rid of this thing."
The primal beast coalesces into the space behind the girl, far larger than her evoker, though still dwarfed by AM. "Of course, my love... I too, tire of listening to it speak..." With a haunting laugh, Death darts forward, swinging her pair of scythes in wide arcs across AM's body.