Hmm, it is an interesting idea. But you still have to get them addicted enough to want to skip the grind.
That's easy enough. Make it free to play, then charge for gold and extra items and junk.
Example: Rappelz. The fact this is still getting updated and doesn't look like crap means this model seems to work.
At no point do you have to buy it, and at no point will you absolutely need it. So to me it's more of a win/win than anything.
This kinda reeks of paying someone else to play the game for you. Via the power level services that sprang up for MMO's. Where people would take your account and level it for you. For a fee of course... Never made sense to me.
They do say a fool and his money are soon parted.
Slightly off topic, Anyone play the free to play Megami Tensei MMO?