If Apple really cared about its customers, they'd stop selling us and our purchase info to individual banks, and instead let the whole world use Apple Pay.
Charging an issuer for the initial card registration is one thing. That requires some back end support on the part of Apple's servers. (Not really, since even that could be done directly from the phone, but we'll let that go.)
However, charging a bank per debit/credit POS transaction... which is strictly between the phone and the NFC terminal, where Apple is not involved at all, is simply greedy blackmail forced upon a bank/credit union in order to be allowed to participate.
That charge, plus the info that Apple requires back from the banks, is what is keeping banks from joining up.
(And to the naive, nope, the charge has nothing to do with using tokenization. That's something which requires no extra effort on Apple's part, was not designed by them, and was already a known method. Nor does it have to do with fingerprint security, since a passcode works, too. It's simply about being allowed to be part of a payment method that is considered to be more convenient... like any other NFC method... plus getting the same purchase information that the banks previously got.)
It costs banks less to pay Apple .15 per $100 of Apple Pay transactions rather than pay out billions every year in credit and debit card fraud reimbursement, not to mention printing up what will be these new EMV chip/pin cards for each new customer that has had fraudulent activity on their account. Banks shouldn't be hesitant at all to use Apple Pay. Let's not forget the money the bank has in it's vault is the customer's and not the bank's to keep locked up for profit. The money that is saved from Apple Pay will be a step towards bettering the economy. Banks will have more money, and so will people because their customers won't be defrauded with a $0 balance in their checking account when they had $700 in it the day before.