One: The art collector is in Beverly Hills, Ca. Meaning he's a real, live, breathing human in the land where seems most of FAA think only bots reside
Two: He's an art collector. Perhaps some day he will buy this image he liked so much he wanted to share.
Three: Keeping the above in mind, consider very carefully how you'd like to respond to him, whether it's a Thank You note or a You Shouldn't Have Done That Note.
Four: Most of the times our images are used, we find them ourselves, there is no credit given, no link given and the image is being used for a commercial purpose. But as Abbie put it so well -- "'Most magical'? And your link is attached?"