Why examples are not run using already running transport-service?

[timov50]

E.g.,

$ docker run --rm -v wirepas_dbus-volume:/var/run/dbus wirepas/gateway_transport_service wm-node-conf list
cons: will pull latest wirepas/gateway_transport_service docker image

Are there reasons why command cannot be executed using already running transport-service, like below?
$ docker exec -it transport-service wm-node-conf list
pros: no need to pull a new wirepas/gateway_transport_service docker image