Many services grant fewer capabilities to a session authenticated only by token. In the case of Starbucks, you can buy a coffee or even reload the card from the

Many services grant fewer capabilities to a session authenticated only by token. In the case of Starbucks, you can buy a coffee or even reload the card from the user’s bank account via the app, but you need the password and the web site to change the user's mailing address. Therefore, this vulnerability might enable an exploit such as draining your bank account into gift cards that I send to my address, whereas access to your phone and token would not.