Is it shady to apply these small monthly fees? Yeah, I think so. But I guarantee you it's disclosed somewhere, so it's kind of on you to notice that type of thing. I think banks intentionally make these fees small so that they generally do go unnoticed. It's like Peter's scheme from the movie "Office Space"...take a fraction of a penny out of tens of millions of transactions and it quickly adds up to significant money.

Something similar happened to me with Wachovia years ago...I've forgotten the details, but I believe they mistakenly applied a fee to a dormant account that dipped my account balance below the minimum required limit. Then they started dinging me every month for a low account balance fee. I knew that the account was dormant and that I wasn't using it, so I had stopped paying attention to the balance, so this went on unnoticed by me for months. Eventually I think Wachovia sent me a notice saying the account had a negative balance, and when I looked into it, I figured out what had happened. I think in my case, because the initial charge was a mistake on their part, I was able to get all of the money refunded when I threatened to close all of my accounts. In your case, if you have no other accounts with this credit union, and if none of the fees were illegitimate, then you probably don't have much leverage. But, it can't hurt to try.