I can't speak for the Geek Squad (as I have never needed to use them), but they price match to Amazon (and several other online stores), and will generally have what I am looking for (at least for consumer electronics). I know that I will get it that day (vs. Amazon's "two day shipping" that regularly turned into three or four days) at an Amazon price, it will certainly NOT be a counterfeit, and I don't have to give…
I went to a brick and mortar store instead, bought the same product for the same price with a well-defined return policy. I ended up not being impressed with the sound and was able to return it without hassle.
For small items where out of pocket return shipping wouldn't be too expensive I'll go to Amazon, but for large items I'll stick to places with a local presence.