First of all, it's not pay to play. It's a bonus to people who pre-ordered the game at GameStop, hence why it's available to everyone else in the outside countries without a preorder. Likely, either GameStop or Sony went up to the other and said "Hey, what can we offer for pre-order bonus?". Someone suggested a demo. Gamestop must've suggested an exclusive demo (again, you guys act like this is some new invention...Rogue Squadron 3 anyone?). This was born, giving Sony lots of money as GameStop surely would've had to pony up to get that exclusive demo. Anyone who thinks this was Sony purposely conspiraced to shoot JF- erm, I mean, not offer this demo to the users is stupid.
If you want me to go in depth on it, I will tommorow. But giving away this demo as a pre-order is no different than giving away beta access if you pre-order. The only difference is adolescents pretending to be internet crusaders.
And again, this is a exclusive time based offer, meaning that once the game comes out, the demo will be available to anyone.

, I bet half of you who are bitching don't even own a PS3.