Under most cirmcustances I would agree with you completely but this one is a bit diffrent.
First is that with a non K series sandy bridge cpu you can't over clock more that a few hundred mhz. So as the computer is nearing the end of it's lifespan there is no option it OC it for a little bit of life support as you would have with any other chip produced.
Second is how low the price premium is for the K series chip. A mere $15 gives you the option to over clock where as the non K series chip has the option completely absent.