That's a really interesting point about calling it a hobby.That being said, I don't like the idea of calling this a hobby. I don't call having a dog or cat as hobby, I call them loving companions.
Why would we when it comes to fish, coral, inverts and all that goodness?
This is called Reef keeping or FOWLR, but not a hobby. All our living beings deserve the same love and care.
FWIW I have fish that have died buried in the yard. (as opposed to throwing them in the trash or toilet)