I'm noticing on a lot of items that have "pre-orders" there are already glowing reviews for the item, which is silly because there's no way you've had a proper opportunity to sit down with the device and really "experience" it when the item isn't even shipping yet. The speciifc item I'm referencing right now is the new Samsung Galaxy S8's, which weirdly enough all have 5-star glowing reviews even though no one has even received their devices yet. But it's certainly not limited to these, I've seen it in the past on pre-orders too.
There are a lot of customers out there that rely on these reviews to make "informed" decisions and a lot of these are your "not so tech-savvy" people that would rather rely on, what they perceive to be honest and informed, opinions [living vicariously comes to mind] and this not only taints the review pool but it also makes people question the validity of other reviews on BestBuy.com as well and you'll recall there was some major fall at a large online marketplace seller over this, this past year that resulted in the them completly over-hauling their review system where it now hides un-verified reviews and only shows them after you specifically click to see them, among other strict changes (i.e. there's a very strict minimum amount of characters and they use bots to scan reviews to make sure they're relevant - i.e. about the product, not the shipping experience, etc. etc.).