Re: Criminals, number spoofing
If the frauster already has access to the SIM SMS functionality (and can send and read messages), why would they need to steal the number? The device is already compromised.
Also the user would notice the phone go offline? There is a perhaps a fraud angle if a voice call is somehow useful but it has to be worth the risk of this method which would allow the user to notice.
There are easier ways to number spoof, transferring it is definitely more authentic but also more traceable.