I'd just send him a note paraphrasing "Look, being a monthly sub for this price is not an issue, but as a patron I'd like to see some material I'm ACTUALLY subbing for. I'd like to see your artistic work with _____. If that's too much to ask and that's how you want to run your business, then all good- but I'll be un-subbing come the next month."
Sorry he's been difficult and wish it wasn't like this.