The beauty is that anyone can request a payment token, so a merchant can store a payment token instead of the real card number.
For example, a merchant doing recurring transactions no longer needs to store the card details. They can request a token that will only be valid for purchases with them for a particular amount. This means that the merchant no longer needs to store card details. This will reduce the compliance requirements for the merchants considerably. The same goes for mobile wallet providers. A lot less requirements needed.