Not really, these are probably mutually beneficial. Having $35 million sitting in a cash account is, as Mitchell recalls in the article, pretty bad -- you're forgoing a lot of benefit for yourself.

What the bank is probably mainly trying to do is not "extract a higher margin" from you, but rather to "maintain your business." While Alex might not have recognized that a startup that took in a bunch of financing and plopped it into a cash account and then didn't do much with it is a customer who might disappear at any time, on some institutional level the bank is aware of it. They want you to regard them not as an interchangeable place that money sits, but as a valued partner who helps you do things with your money, and as a result you feel like it would both be a risk and a bother to extract all your money and go to some other bank.