Confused about the goal of these examples

[ChrisMoriarty]

I'm still in the early phases of ramping up on github actions, so forgive me if I'm just missing something. I just took a look at redis-service.yml, and it seems like the workflow is doing the same thing twice. Once in a container, and once in a virtual machine. Is this the point of the example? Wouldn't it be more useful for the vm-job to connect to the existing redis set up in the container? Is that even possible?