But will this run inside another docker container?
I normally hate things shipped as containers because I often want to use it inside a docker container and docker-in-docker just seems like a messy waste of resources.
Docker in Docker is not a waste of resources, they just make the same container runtime the container is running on available to it. Really a better solution than a control plane like Kubernetes.
No, you're running docker inside a docker container. The container provides a docker daemon that just forwards the connection to the same runtime. It's not running two dockers, but you are still running docker inside docker.
I normally hate things shipped as containers because I often want to use it inside a docker container and docker-in-docker just seems like a messy waste of resources.