It is an odd piece of grammar, but I've heard it fairly often. I'm not sure if it's proper English or not. "many, many" is a different way of emphasizing the w

It is an odd piece of grammar, but I've heard it fairly often. I'm not sure if it's proper English or not. "many, many" is a different way of emphasizing the word "many". So "assessed many, many fees" implies that there were more fees assessed than if they had just stated "assessed many fees".