I'm not sure where to stand with the GTAIV issue, as far as where I stand currently, there is no form of downloadable content that has to be paid for that is acceptable; in that they are endeavours to perfect the game and not just ways to milk specific demographics.
I'm seeing it from the eyes of children who play these games, even if they aren't supposed to, but these kids will grow up, and these games will be replaced with other games that could recquire something more streneous on a wallet. Kid's don't have access to a credit card without their parents.
Back in the late 90's this method was used for age verification, but now it's used to garner a companies profit margin - when I see a game rated EC and has downloadable content, maybe others then a mass will also believe that this has gone too far.
For myself though it's not really an issue as DLC and P2P got me out of the PC gaming scene and I'm just looking for a reason to abandon console gaming as well.
This is just me viewing it from the lense of a PC gamer I guess, most guys who have been playing PC games for at least the last 15 years have an idea where this is going, but that may be a brash assumption on my part.