You are a gamer if you go home and are excited to boot up your pc/console and play a videogame regularly. Regardless of the amount of games you play, the spirit is all that matters. Would a person that only plays/practices one game in order to be competitive at it not be a gamer? Besides, WoW requires a lot of time commitment and the classic game people think of when hearing the word "gamer" is probably world of warcraft or LoL. LoL people basically only ever play LoL. They can spend hours talking about patch notes for some champion buffs and how 2013 *Insert Champion Here* was so fun.