All of those services accept credit cards. Because there would otherwise be too many people unwilling to give up their bank routing number.
What you need is something that has irreversible transactions but also has a monthly total transfer limit and a "routing number" which is unique to the merchant and can be revoked for further transactions at any time. Ideally also something that allows people to make purchases on credit and earn "points" so it's competitive with credit cards.
That way people would actually be willing to use it, instead of having to give a startup with no reputation (or a company with the foul reputation the likes of PayPal) access to their entire bank balance.
