It's obvious, but why don't we do it more?
When I was younger I would (snail) mail my favorite athletes with a self-adressed stamped envelope (do these exist any more?) asking for an autograph, and most would reply. Or they had people to reply.
As I got older, I would write my favorite authors, as the writer here did. Again I would get a lot of responses.
An adage in customer service is "One angry customer generates twenty times the PR as one good customer." If you are the one happy (raving happy?) the creators are happy to hear from you. Most creators (deliberate word choice - creators) are in it for more than just money. A lot of creation is about self-fulfillment. But to be deeply appreciated... Ah!!!!