You're the sucker if you pay big bucks to Microsoft for a Retail product key instead of a cheap OEM key from the internet.
If you don't know what an OEM key is then Google it.
At any rate, even if the product key I bought from that website is a recycled one, it makes no difference because my current Windows install is showing as Activated and everything is working as expected.
You have to type the product key in manually you know, there's no crack or keygen program involved ergo zero risk of virus or malware.