I've been running these events since June 2022 and don't charge for the events. I make income from other sources and It doesn't cost me much to keep the events going. It's something I love to attend myself, so for me, it's a bit of time out, a chance to meet a few people.
However if you do feel strongly about supporting the Coffee with Arthur journey you can always drop a small tip here. Whether you do or not, the events will still go on!