Once I tried to make two payments because i was late the previous month. They manually decided that I must of made a mistake and failed to make one of the payments (they assumed it was mistake and never notified me). As a result my insurance was cancelled and renewing my policy cost me around $1700. That was at BOA 20 years ago and I've used credit unions ever since. Since I was barley getting by at the time I had no recourse.
So, you have found it to be true.
In all these cases, I could not get the fees reversed on the phone, but had to visit a branch in person, where the branch manager was indignant that I had the gall to rob the financial institution of their fees. I did get the fees refunded. And two weeks ago, I closed all my accounts with them.
I am fortunate to have a community bank that acts the way my credit union once did. The only quibble I've ever had with them is with the staff not knowing the rules on overdraft fees.
Customer friendliness can vary a lot even within a bank/credit union depending on the customer and personal banker, since a lot of fee waivers are discretionary. E.g. if a banker has a fee waiver limit per month then they can help you at the start but not later in the month.
Part of the issue is that since rates have been so low, the traditional net interest margin of banks has been squeezed so they turn to fees to compensate.