That is where the confusion is... Sites like this are usually setup as a legit site a user will access and they usually request for a cell number and also accept access to info or a site.
This method is how the user is tricked into authorizing the Premium Message charges.
Since users have habit of not reading everything they agree to, the spammers use this method.
Spam text are forbidden are there is strict legislation that prevents rogue companies from charging without proper consent.
Stopping the service is one thing but getting a refund is equally important. These companies are counting on the fact that for every 100 people they bill fraudently a small percentage maybe 10% would seek a refund possibly even less. So dont be part of the 90%, its your money claim it ALL back
If you need help contact me.