Yes, if you freeze deps you can just install to the system paths in a Docker container. But most people who I've distributed Dockerized ansible git repos to don't read the README and don't try to run it in Docker, so they flail around trying to get it running without a venv or anything, until I finally convince them to just use the container (they're not familiar with containers either so it's almost as much of a slog).
Isn’t the point of Docker that not everyone has to know the virtual envs, etc?