In Australia, Telstra is required to keep the payphone network up and running. You can make free outgoing calls to landlines and mobile phones. And I just read that you can call inbound as well (which I did not know). Now the fun begins.

Telstra are one step ahead of you and encouraging an ingress style territory control game with the payphones.

https://www.telstra.com.au/exchange/what-is-payphone-tag--th...