I also receive free text messages from my provider (Edit: e.g. the texts that say 'thank you for paying your bill'). Does that mean that I'm connected to every subscriber on the network that also receives these free texts?
Recently I got a pair and they did help: http://imgur.com/a/03Ipl , but as always this is what that companies FAQ says about the process:
WHAT: ----- Wireless Emergency Alerts (WEAs) are free wireless notifications that are delivered to your mobile device as part of a new public safety system provided by Authorized Senders. They are designed to inform you of imminent threats to safety or missing persons alerts in your area.
In order to receive WEAs, you must have a capable device and be located in an area (e.g., county) targeted by Authorized Senders to receive the alert.
If every provider has some sort of program like this that connects everyone on that network.