Cisco makes the devices and the network management software Meraki. If you have service from Spectrum, you could probably run the service through to those devices, and then to keep track of what they are for an administrator probably altered the ESSID's via Meraki to reflect it and this is why they are named as such.

It is a bit strange there is that many if they are serving some service from Spectrum, but this warrants further investigation to the immediate physical area. Does the grocery store or a nearby business have a lot of TV's or some such? It's hard to say what the devices actually are for, but my best guess as to where I might see something like this is a place like a sports bar where there are many multiple TV's with their own boxes so that they can show multiple sports broadcasts simultaneously.