Your thread had nothing to do with Site Support, and, as noted, the ethics and implications of the cars are being discussed in several other topics around the site.
I share your concerns about what the hacked cars could and are doing to the integrity of GT5's online racing, but to suggest GTPlanet is somehow at "fault" for the existence of the cars or "promoting hacking" is absurd. We don't allow any discussion about how to "hack" or modify the PlayStation console, and can do nothing to prevent players from using, sharing, or trading the cars in the game.
To prohibit any discussion on their existence, which I presume is what you're arguing for, would be a laughably naive policy.