The idea is that the content shouldn't be there in the first place - that it's an additional supplement which complements the original but isn't essential. Personally, I don't mind paying sixty bucks for the game and extra for the supplements. One thing Rockstar always does is pour quality into their GTA games. They're always bursting out of the seams with a lot of content and things to do. If they're going to put up extra stuff for purchase, I trust they'll be meaty.
It's like buying an expansion pack.
It doesn't matter. Lots of things are included in games which arent "essential". The Zelda games have tons of extra minigames and whatnot that aren't integral parts of the game itself.
$60 for a game is ridiculous enough. To have to pay any more is worse. That was the one thing that almost made me hold out for the PS3 instead of getting an XBox. Because, to make it even worse, with XBox you have to PAY for the ability to even buy these "extras" in the first place!
I have not, do not, and will not ever pay for extra content. It's asinine that anyone would even consider it.