Hasn't Apple removed a lot of games for various reasons? I bet if they ever became fully aware of the lyrics/dialogue, the games would be removed.
edit: I should clarify. Every once in a while I see news about a game being removed, usually for being controversial, often outright vile (like that baby shaking game). That indicates that Apple isn't looking too closely at their store- not surprising, isn't it overwhelmed with shovelware? So some games squeeze through the approval process and then get taken down later.
I'm not sure what, if any, games have been taken down for hard-to-justify reasons. I am not an Apple fan so I don't go searching for this stuff. I'm not sure what would happen if someone complained. Some anti-game nuts will go after anything... they tend to get shrugged off... with respect to Western games at least.