Pilar does not feel like doing so.
...how does she actually leave the Fortress? The Securities wouldn't stop her... probably... well, no, they'd ask questions. Those questions would have weird answers. Security might ask Pilar to wait while they queried upwards if she's allowed to leave. Pilar... doesn't feel like living through that.
How does Pilar just, do the thing that everyone thinks of as synonymous with Cake Girl, where she just suddenly is somewhere. It's always been Snack Service doing that, before.