I know that is true for me. But does it apply to all? How explain the desire for more of the same, then, in a large part of the audience?
It could be because, apart from a relatively small 'hardcore' part of the audience, people don't really play that many games so they don't particularly care if they're all pretty similar.
According to
this article only 8 games have been sold per xbox 360 and 5.3 per PS3 which isn't necessarily enough for them to start getting bored of seeing the same things over and over in videogames. (Although those statistics may have changed a bit now since the article is 4 years old.)