As you've found out, if there's nothing physically wrong with the shoe (i.e. none of the zoom bags have popped, or the fly wire hasn't ripped, or your foot hasn't torn out of the shoe) you can't return the shoe to Nike get your money back. If you bought it from Footlocker or Finishline, you could try taking it back there (if you still have the receipt) and see what they can do for you. Sometimes they might give you store credit or something.
That being said, if these shoes really aren't working for you, I think these are your options (not in any particular order):
1) Damage the shoe in some way. It sucks that you have to resort to this because you're taking advantage of Nike's system, but if you try cutting the fly wire closest to the toebox (i.e. first and second lace holes) (not a clean cut, make it look frayed/like it ripped on its own accord), Nike will most likely give you a voucher for the full retail of your shoe, which you can use to buy whatever you want on the nike online store. This is the closest thing to getting your money back, especially if you want to stick with Nike shoes. It won't work though if you've already sent in a bunch of stuff to nike through their voucher program. Details on that
here.
2) Take it back to footlocker/finishline if you bought it there and still have the receipt. No receipt and you probably won't get anything. With a receipt, you may at least get store credit.
3) Sell the shoe. Sell the shoe through a local facebook group (Kream is good if you're in the Chicago-land area), or through craigslist. You probably won't get full retail, and will most likely take a loss, but you'll get some money to put towards a new shoe.
4) Trade the shoe. See if someone will trade for a different shoe. Again, you can use craigslist or a local facebook group.
Sorry for the novel. Good luck!