I keep reading the description but I'm really struggling to come up with a common use case for this. A number of ISPs in the UK (I think both BT and Sky) used

I keep reading the description but I'm really struggling to come up with a common use case for this. A number of ISPs in the UK (I think both BT and Sky) used to do something similar (possibly still do), where you would add a special network to your router that was only open to other people who also added the network to theirs, so you could use each others when out and about. It was all tunnelled and secure. It was genuinly useful in the days before 4G mobile and widespread wifi in shops and cafes, I used it a lot. With this I just don't see what devices would be using it. It isn't something you can just piggyback on to check your email. It feels like this is preperation for some new device or service. Or am I underestimating the number of people who want to put an Alexa device somewhere that they don't have a network, but which is close to someone elses network?