Based on sales primarily.
With the Vortex Razor HD receiving "product of the year", it is highly unlikely that is based on sales. Do you know how frigging expensive the Razor HD is? I imagine it's a very small percentage of shooters that can afford one. It is an excellent scope, I have used one that a friend owns (but I'm not rich enough to own one myself!) I can't imagine they sell very many of them.
"MOAR - Reticle of the year". That can't be based on sales either. Like the Razor HD, not many shooters can afford a Nightforce scope either. Which probably equates to a very low percentage of shooters having ever seen a Nightforce MOAR reticle.
The two things above are excellent, but I don't see any way that they could be in this "best of" list based on sales numbers. Top notch quality and design, yes, sales numbers, no.
Other things on the list, I'd say are definitely based on sales. "Plano - gun case of the year". Say what? But I'll bet they sell tons of them, simply because they are cheap.
"Cold Steel - Knife brand of the year", "Glock - Pistol manufacturer of the year". Must be based on sales. There is nothing special or exciting about Cold Steel or Glock. They are both decent enough, but certainly not "best of" anything. Except maybe total sales.