Ask HN: Why isn't Amazon the largest online wine, beer & spirits merchant?

What is it about over the internet alcohol sales that prevents Amazon from being the largest online seller of wines, beers and spirits?

I would imagine that it would be trivial for them to add an age verification process where a user verifies his or her age with government issued ID and takes a photo of his or her face, then at checkout, they take a photo of the user at checkout with the getUserMedia API to confirm the person buying alcohol is the same person who verified their age.