it is not just that. watching someone play a game (be it video games, sports or board games, whatever) is different from watching them watch a movie or read a book. games can be experienced in unique ways, and once you get the experience yourself you may enjoy saying other people experience it in different ways. sharing fun is nothing to be ashamed of.

the only thing to watch out for is not letting the filter of enjoying something through other people's enjoyment be a replacement for you enjoying things on your own in general. you should be able to do that for your own benefit.