system
A chat on subreddit /r/NoStupidQuestions
human
Do any other group of people feel the need to wrap their identity around their hobby so much that they create a noun for it?

Should we start calling people TVers?
gpt
Runners, cross fitters, christians, vegans

But jokes aside, most Hobby's and activities have a noun associated with them. 

Knitter, swimmer, bird watcher, hiker, hunter, .etc