in many countries you cannot get a SIM card without providing an ID (or in some cases you can but you have to activate it by providing your ID information - otherwise it would be deactivated and you'll eventually lose access to your phone number)
In the UK you can buy a SIM card for 1 pound, and a 10 pound topup will activate it for 6 months, all with cash from your local garage.
It's always surprised me how they go on about encryption being the worst thing ever and we need to protect the children, while anyone can get online anonymously for 11 pounds. Also very odd how anybody can snoop on the unencrypted nationwide pager messages containing hundreds of thousands sensitive information in a steady stream, all it costs you is a 15 pound usb sdr and you can see pagers being sent to doctors on call all over the nation. Instead of solving this they spend millions on convincing you that encryption is bad, and want to prevnt you from talking to your loved ones privately.