The problem is that Apple PR always tries to make it sound like they invented something and/or are exclusive with it. (E.g. the "220,000" NFC spots which already existed.) This confuses people, which is of course their intention.
Yes, that's likely part of it. Also see post above about having to support tokens, either themselves or via their processors.
Yes, however, the Apple Pay device account number tokens are not one time tokens.
They're static token numbers with a special bank id prefix, and are provisioned once per device. (Up to eight iOS devices can point to the same real account number. Each will have its own particular token associated with that real account number.)
The tokens only need to change if your device is stolen or your real account number is compromised. (Actually, for the latter, they could in theory simply point the same device token to a new real account number.)