You're assuming the telecom operator of the SIM farm doesn't know his customers. That'll change very quickly after the first few have to cover the fines themsel

You're assuming the telecom operator of the SIM farm doesn't know his customers. That'll change very quickly after the first few have to cover the fines themselves. After that that scam would result in the scammer paying the (e.g.) $10 upfront, the (up to; e.g.) 10% for every hop between networks and likely and transaction, processing and legal fees for the civil case (if he's not cooperating). And he'll likely end up with criminal charges on top of that. Also it's not like the scammer gets sued by some powerless private citizen authorities are likely to ignore. His opponent will be a telecom provider in his own jurisdiction.