That's your route to profitability? Offer lower rates on savings than private banks?
The whole point Sanders is making is that there are millions of individuals who don't have a private bank account, and are cut off from many modern financial services as a result. Direct deposit, for example. Such people have to resort to these bloodsucking check cashing services which charge high fees.
The postal banking system would not compete with private banks. It would be supplemental.
Yes, it's sad that poor people have no money to open bank accounts.
Will the Post Office be providing these check cashing services for free?
And as asked above, will they require photo id of their poor, minority customers?