Curious kustomize behaviour - `kustomize build use` will apply the transformer to the generated secret but not to the local service

shared-kustomization.yaml

---
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
generators:
  - my-generator.yaml
transformers:
  - my-transformer.yaml

shared-my-generator.yaml

---
apiVersion: builtin
kind: SecretGenerator
metadata:
  name: mySecret
  namespace: whatever
behaviour: merge
literals:
- FRUIT=apple
- VEGETABLE=carrot

shared-my-transformer.yaml

---
apiVersion: builtin
kind: PrefixSuffixTransformer
metadata:
  name: notImportantHere
prefix: baked-
suffix: -pie
fieldSpecs:
  - path: metadata/name

use-apple.yaml

---
apiVersion: v1
kind: Service
metadata:
  name: apple
spec:
  ports:
    - port: 7002

use-kustomization.yaml

---
apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization
resources:
  - ../shared/
  - apple.yaml

Before running, put the files prefixed with use-* in a use/ directory and those prefixed with shared-* in shared/. Notice that the mySecret resource is transformed but the apple resource is not.

$ kustomize build use
apiVersion: v1
data:
  FRUIT: YXBwbGU=
  VEGETABLE: Y2Fycm90
kind: Secret
metadata:
  name: baked-mySecret-pie-tt72hh58h8
  namespace: whatever
type: Opaque
---
apiVersion: v1
kind: Service
metadata:
  name: apple
spec:
  ports:
  - port: 7002

Makes sense now that I look at it again: the transformation is performed before the resource is "imported" into the other kustomization, rather than being a shared configuration.