None of that works or even makes sense if you have end-user devices. Nodes are not interchangeable, you can't route around breakage (if one point of sale goes down, that's one physical device with a dark screen, adding one pod somewhere else won't help), the networking is mostly useless, zero-downtime impossible (you have only one physical screen to use, can't have two containers grab it during a rolling upgrade), service discovery is irrelevant unless you are running your database on those cash registers for some reason.
Use Ansible/Salt/... instead. Kubernetes is hype, and it's what people know, and it can technically do some of those things, but it's a terrible tool for this job.
