Xbox 2/360 to feature online mini-purchases

Don't panic yet, there's still hope that Microsoft will offer free downloadable content for the next-generation.  Of course, for some, that hope is fading fast. 
Microsoft's J. Allard recently described the mini-purchase function that will be built into the Xbox Live community.  Reportedly, players will pay between a dime and a dollar to purchase, say, a really tricked out car for their favorite racing game.  In this sense, the mini-purchase system is more-or-less the lazy gamer's road to success.  But how will this affect competition?  How does Microsoft plan to reward the gamer that plays hard,
but isn't willing to buy the next level?

[Thanks, Chron']