How does all this make money? Each individual track, or "stem," costs $0.99 on iTunes. So that's $5 right there, and that's assuming you don't also end up buying Phil Collins's entire No Jacket Required album ($9.99) since you're already on iTunes anyway.
So when all is said and done, it's pretty much a safe bet that you'll be about $15.00 lighter as a result of all this (though you will have "Sussudio" to jam to). Don't tell me these marketing people don't know exactly what they're doing.