Most people should grow out of that at what, eight years old when they learn how to play most games themselves?
So most people should grow out of watching soccer at age eight? Because, *anyone* can play soccer, right?
People don't just watch video games on Twitch because they are scared of playing them...I'd say those numbers are insignificantly low. People watch video games on Twitch for a variety of reasons: they like watching people play the game who are way better than they are, or are worse than they are (slapstick funny), or to learn strategies, or just for plain straightforward enjoyment of the medium on it's own.
As Kaytoue et al state: "watching video game live streams tends more and more towards becoming a new kind of entertainment on its own."
As Marshall Mcluhan said: "The medium is the message".
Kaytoue, Mahdi, Arlei Silva, Loïc Cerf, Wagner Meira, Jr., and Chedy Raïssi.
“Watch me Playing, I am a Professional: a First Study on Video Game Live
Streaming.” Proceedings of the 21st international conference companion on
World Wide Web. New York: ACM, 2012: 1181-1188.