But yes you have a point there ...a Xeon produce 300kh/sec an i7 400kh/sec. It will consume a bit less (half) and give more with 30% .
See, and you can keep tweaking those numbers. I'm only running 4 threads, my i7 is not even the very latest generation model, it is at standard clocks, and my hashrate is 465 kh/s. I have high electricity costs, and yet it is profitable for me, if I chose to simply dump ZRC > BTC > FIAT (which I don't).
So if it's profitable for me, why would it not be profitable for someone with a rack of recent servers, probably paying a lot less for kW/h?
If I had such a rack of servers, I would certainly mine with them. This is valid for someone that will immediately dump the coins, as well as for someone that just wants to hold them long term...
Point being: none of this implies the use of GPUs or CPUs... Adding such big hash to the network, only shows that it is someone with large computing resources at hand. Heck, I could own half the nethash for a few hours if I really wanted to spend a couple of BTC on server rentals. I am not saying that would be the smartest thing to do
Edit: I see othe just posted how many spot instances it would take. There you go!