How did Wells Fargo intend to profit by opening up two million fake accounts?

In 2016 Wells Fargo was fined $185 million dollars by the Consumer Financial Protection Bureau for opening up two million fake accounts, that is accounts without their customers permission.

Q. How did they intend to profit from this as it seems that no new money was going into the system?

edit

@Giskard: Unauthorised accounts are still a fake accounts, it’s merely more specific about the nature of its ‘fakeness’. I meant by new money as additional monies brought in by new custom. Your answer points out that Wells Fargo was making money through administrative charges as opposed to interest on a larger capital base. I’d have accepted your answer as correct but my phone isn’t letting me click on accept – it’s an old phone.