No reason to spend ~$300 on a CPU that can overclock and then use the stock cooler.
The stock intel fan does come with pre-applied paste as mentioned, but it is woefully undersized for the CPU and especially undersized for overclocking. There are plenty of aftermarket CPU coolers in the $20-30 range that will be quieter and allow your CPU to stay at boost clocks longer. (Cooler Master TX3 is about $20) For mild overclocking there is the Hyper Evo 212 for ~$30-40, it is rather large)
Many aftermarket CPU coolers come with paste pre-applied or a small tube (or baggy) of paste to apply manually.
I do plan on overclocking eventually.. but right now I'm over my build budget and I'm buying as much as I can, when I decide to overclock I'll definitely get one of those fans