Don't get me wrong, I'm not saying that a midnight release wouldn't have been better, but I think that you're demonizing it a bit too much.
Middle of the week, almost everyone is at work/school and they don't necessarily have a game shop in a walking distance. For people like that, who want to enjoy playing during lunch or whenever, this preload is perfect.
Since the retail system in Japan is a bit different than the one in the US from what I've heard (publishers get money for their game when the store, not the customer buys them), they really don't want to push dl versions too much, since it's basically game over if Tsutaya/Geo/Yodobashi/Bic/Yamada/Joshin turn their back on them.
And 12;00 is probably just the scheduled PS Store update time (although stuff sometimes shows earlier), so I wouldn't look that much into the 1-2 hour difference.