This is a case of you buying a Core i5 and Intel saying "here is exactly what you paid for, and by the way, if you ever decide you should have bought a Core i7 instead, we can magically teleport one into your computer for just $50".
Well if they can afford selling me an i7 for the price of an i5, even though I might never unlock, why don't they just go ahead and do so? I don't understand, is there a reason why processor must cost a certain amount of money, even if all the expenses going into making them are less?
If indeed the company runs out of low end processors, and starts selling crippled high end ones, why bother crippling them? Just sell the high end unit for the low end units price, hell call it a sale or limited time offer or whatever. Won't more people buy an i7 than an i5 if they were the same price? It's not like they're stuck with it later either, I don't think Intel is seriously unable to say, "sorry guys, our stocks are properly balanced now, back to the usual prices".