> Not true by any means. Fiat is the tried and true way to commit crime.

Depends on the crimes, and up to certain values/volumes.

For 'consensual' transactional things for goods/services it could be useful (e.g., drug deals). But for ransom-like stuff, where one end of the 'transaction' is not thrilled with the 'deal', having to physically pick up the cash puts the perp at risk.