It seems like you're using a very liberal sense of the word "viable" if "Authors could set up their own stores" is considered a viable alternative to selling on Amazon.
I'm not sure I see the relevance. Lots of people do lots of different things. Some people juggle geese. Does you having bought books from authors who set up their own websites mean that bespoke websites are a viable alternative to Amazon for the majority of authors?
Of course they are viable. The ones I bought from were set up because the author didn't want to deal with Amazon.
It's never been easier for an author who wants to sell his own books to do so. It also isn't hard for like-minded authors to pool their resources and set up their own sales site.
Maybe this is true, but I hope you'll forgive me if I do not take your totally unsubstantiated word for it. Is there actually a good reason I should believe this is viable? Because I have seen no evidence of that whatsoever and a lot of evidence to the contrary (chiefly, the paucity of authors succeeding using this supposedly viable option when compared to other avenues).
