not many rational gamers will buy multiple copies at the same time.
i actually have an idea. Sony can allow gamers to download the NGP version for free as long as the ps3 version is registered on the same psn account. Apparently, it will require serial numbers to register the game. But the gamers can get NGP games for free and it is only a small cost to publishers (royalty, which Sony should offer discounts in this case). It's a win-win really.
There is a complication though. Gamers can choose to sell the game to gamestop and keep the NGP version. To remedy that, I think it also needs a de-registration process, which requires the removal of the NGP version. The serial number cannot be re-used unless the de-registration is completed. The used game buyers then need to check whether the game has already been de-registered before handing over the money. In this way, used game market is still happy and at the same time, no one is going to keep the free games.
just some random ideas. probably sony will read this... unlikely.
