Intel has made it official that it will not let the non-K series processor, say Core i7-4770 to be overclocked. So yes, while Haswell gives you more flexibility in the form of additional base clock straps, these straps have been disabled in non-K series parts.
This implies that overclocking is only available in K-series processors like Core i7-4770K. This series is $20-30 more expensive than their non K-series counterparts. For instance, Core i7-4770K is $30 more expensive than Core i7-4770.
If your buying a top end i7 like this why wouldn’t you get the K version. Some people don’t like to overclock which is fine, but why even bother making the non K model then.