As for the transactions vs hashes correlation, while technically true, in practice the two are inevitably linked, as the currency must be protected proportionally to the sums it manages. As more value is stored and transacted, so the incentive to attack it increases, and so an increase in the cost of attacking it is required. Though it might trail off at some point, Bitcoin's history has shown this relation to exist.

In practice ACH transfers within the United States are free and clear within a few days(giving you time to catch fraud). There's also very little technical barrier to transferring money abroad, although there is risk to the bank.

Credit cards are a different matter. They have to clear instantly so the merchant is guaranteed payment(excepting a chargeback). Bitcoin (usually) clears in an hour, or at least 10 minutes, so it's unsuitable for realtime financial transactions unless you build a financial industry on top of it to mitigate risk.