The hardware is less important than the merchant account. The risk of charge backs means a small business accepting a credit card is effectively taking out a loan. Apple isn't going into that part of the value chain (so far).
Right, Apple is only providing the hardware and it requires to use a (partnered) processor, like Stripe, which was the example they used in their recent announcement. Stripe coincidentally sells chargeback protection as a service https://stripe.com/radar/chargeback-protection if that is a concern.
