I don't know what Intel and Asus are thinking. It's frustrating to see such a high price premium for Thunderbolt on desktop PCs today. One has to buy a new motherboard (~$200) and then buy an add-in card (~$200) to get a working Thunderbolt port.
The Thunderbolt cable is currently going for $50. So, that's $450* if you wish to utilize a thunderbolt device. I know people who spend that much on their entire computer!