The Public Purpose Of Banking

Food for thought: Attention Lloyd Blankfein: The Public Purpose of Banking,

… WHO controls the banks is ultimately less important than HOW we control the banks’ activities. Oversight is all very nice, but at times it pays to get back to first principles. What on earth is the public purpose of these things? [emphasis added]
[. . .] Newsflash: the public purpose of banking is NOT to provide profits per se to shareholders. Rather, the provision of the ability to earn profits is only a tool used to support the attendant public purpose.

WHY do we have corporations in the first place? Who is our economy FOR, anyway?