They have lots of illegitimate use that isn't about crashing the cell network like sending out spam https://www.cyberdaily.au/security/9949-sydney-man-arrested-

They have lots of illegitimate use that isn't about crashing the cell network like sending out spam https://www.cyberdaily.au/security/9949-sydney-man-arrested-over-massive-sms-phishing-operation https://www.cyberdaily.au/security/9949-sydney-man-arrested-... or allowing people to use in-network free call allowance to instead make voip international calls