Bioshock Infinite Pre-Order Bonuses

With the much anticipated game (sequel? reboot?) being released next month it seems that publisher 2K is trying to gain more publicity and profit right out of the starting gate. Available to those who pre-order Bioshock Infinite on Steam, the titles of Bioshock and potentially X-Com: Enemy Unknown will be included as free bonuses along with Team Fortress 2 exclusives.
Yes, it's hats how did you guess. 
As a further bonus to Infinite itself, all pre-ordering buyers will also get the Industrial Revolution Pack - Bonus content for the game which includes 500 of the in-game currency, five lock-picks and the Industrial Revolution puzzle game.  

There's just one small catch to this - Much of it is based upon how many of your friends are also going to be pre-ordering. 

The inclusion of each additional title is being based upon a tiered system which unlocks a free bonus game or content. As the numbers of pre-orders go up more tiers are unlocked and the more things become available. Though the Industrial Revolution Pack was always intended as an included bonus. Thus far only the first tier, the original Bioshock bonus, has been unlocked and the pre-order quota is only nine percent towards unlocking the second tier. 

Purely on a marketing level this is an intelligent move for a good number of reasons. The most obvious one is in terms of early profit. 
With so many people pre-ordering the game early on prior to any true feedback or reviews it means that no matter the reception Bioshock Infinite will be making the creators a great deal of moolah. The last really big case of this was with Aliens: Colonial Marines which utilised a vast number of pre-order exclusives and bonus content to make an early start and earn Sega far more money than they otherwise would have gotten with the game of its low quality. More importantly however this can easily work off of word of mouth and can be used as incentive to encourage friends to also pre-order in the effort to get additional content upon buying. 

The more of them convinced, the more games (all of which were critical successes) the person who encouraged them to sign up gain access to. It won't register as any kind of scamming on any real level because everyone benefits and they are not being asked to sink any additional money into it they wouldn't be spending on release anyway. Furthermore even if they don't agree to buy the title there is still free publicity being made out of them talking to one another. 

 If the actual scheme itself wasn't enough proof of this, a post on Irrational Games' blog speaking about the pre-order bonuses had this to say about it - "But to unlock all these rewards, you’ll need to spread the word and work as a team". The sorts of words which encourage people to turn from customers into promoters of the title.

Perhaps the biggest point of concern however, is that Steam does not permit pre-orders to be cancelled once the game is released. So while you might get some genuinely good content, if the game is bad you're going to be stuck with it and with no way to trade it back in.
Despite the good track record of those involved in the game's creation and distribution this is still a point of concern. Whether or not this is a marketing plot to make money out of a title which  would otherwise not receive many purchases or is an effort to get some additional profit while having their customers get something out of the deal is just something we'll have to wait and find out the answer to.