It's not highly publicized, but it is in fact easy. And if there are lot of users reaching to him for refunds, he needs to improve the app because it's not as advertised. I doubt he's actually getting a ton of refund requests though. It is a thing that happens though, and when it does you inform that user how Apple's refund process goes. No reason to eat $4.50 every time.
I'm not this developer, but if so many users are reaching out to them for refunds, then there is a definitive gap in store functionality.