Banks basically don't use database transactions to record financial transactions. Instead, failed operations are rolled back with an inverse operation. It's done this way to ensure that there is an audit trail of every operation, rolled back or not.
I would assume that banks can be the best enterprise profile user of event sourcing. For traditional application we use the DB rollback for failure mitigation and banks are actually explicitly doing that. I think the event is already there and they are essentially using the same concept as event sourcing if I'm not mistaken.
And I think its much easier to make it work. There is a lot of associated domain and logic but the core of banks is a series of transactions (never worked so could be completely wrong) .. source, destination, amount. It looks poster child for event sourcing/log based architecture.
