Most times, the financial institution will eat the ACH fee, so to the customer it looks like it's free.

SEPA also doesn't mean that the transactions are free, either. According to a third party transfer service (https://transferwise.com/help/15/paying-for-your-transfer/29...) there might still be some fees from banks.

If you do commercial SEPA Transfers, yes there are fees. If you only do push transactions (ie, customers sends SEPA transaction to you), it's largely account management fees.

The pull transaction (SEPA Debit) isn't free, you can buy transaction packets (usually around 5-15€ per 1000 transactions) as well as paying a fee on monthly cash inflow (usually around 0.1-0.3%). Honestly, it's peanuts.

Naturally the UK banks found a way to charge consumers for SEPA payments.

SEPA can be free for customer but participating banks and payment institutions pay per transaction.

I had this random thought, I wonder if it holds water:

The EU states are (fairly) confident in their status as independent countries, and thus dare subject themselves to and implement such things as SEPA.

While the U.S. is a single country, the states within are not independent countries and, very aware of that, try to defend their independence within the union at every turn.

I'm not sure it's the independence being defended so much as local grift of one form or another.