Laws are meant to control criminals, not the innocent. All telecoms have the ability to track their traffic and a reporting system combined with automated monitoring of activity can allow for numbers to be disconnected automatically for suspicious and/or illegal purposes.
I keep having 541-246-9013 call me. Sometimes it's once a day. Sometimes a few times throughout the day. A few times, it was multiple times, one right after the other. One time it was 9 times in a row. Once in awhile a silent 4 second voicemail is left.