Maybe because a lot of music gamers like is video game music, and to a large percentage of the ignorant, pompous; stuck up, snooty; pretentious people who listen to "real music" from "real composers", video game music is just a bunch of "bleeps and bloops". I'm always the first to call bullshit on this and slap those people in the face, because what video game music has that bands don't have is variety. I could name you 100 awesome video game songs and every single one of them would sound completely different, wheras if you were to name the top 100 "real songs" from "real composers" I can guarantee you that about half of them or more would all sound exactly the same.
Though to be fair, with this post I may be confirming this stereotype, so take this as you will.
Though to be fair, with this post I may be confirming this stereotype, so take this as you will.