While knocking Geek Squad and Firedog is way too easy, they are what they are. Most of them only know what the manual tells them, and have never worked with or on a computer before they were hired there. Those who know computers may work there, buy usually not for long.
I considered working for the GS, but decided not to bother. I have my own way of doing things and am not gung-ho with doing it a different way. There are also some thing s I WILL NOT install on a computer, such as Norton that they like to push. I use a lot of freeware when I work on a computer, and these work as well or better than the majority of commercial products available, but wouldn't be allowed to do that there. I charge a very fair price for my work, so their price scheme would definitely go against my own judgment.
Back on topic... I have no Windows sticker on my case as it is not a pre-built. I do have the key in a couple of hard copies that I have put away for safe keeping, though. I have also used a couple of different programs to retrieve my keys to various programs and Windows. Any repair person who actually has the audacity to state that a computer that doesn't have a Windows sticker is not running legit needs to be punched squarely in the mouth, have his pinkies severed, and be barred from ever touching a computer again.