Why Aren't These Books on the Best Seller Lists?

I continue to be baffled by seeing the same old books and authors on the fiction best seller lists.  If you're reading this, you know who I mean.  Two books I've read recently should be inching their way up the lists and getting the attention they deserve, but the stale stuff is entrenched and blocking the way!
The first one is The Sisters Brothers by Patrick deWitt which is a marvelous story set during the brutally lawless Gold Rush days in the American west.  It's got four stars on Amazon and this is what I wrote as a comment on that site:

I really enjoyed reading this very well-written book. What talent to be able to bring the West of the Gold Rush era to life the way deWitt has. In our somewhat sterile, digital age, we forget the brutality and lawlessness of parts of our American history and deWitt has pushed it to the surface in its rawest form - hapless gold panners, pitiless killers, abject whores. The brothers are no better nor are they worse than their peers as they try to scratch out a living in a menacing, unpredictable world. But this is not just a tale of two killers on a mission; there are many scenes of heart-breaking tenderness as Eli, the younger more sensitive of the brothers, seeks connections, understanding, and finally, really, the warm cocoon of love. The scenes where he discovers the joy of tooth powder to brush his teeth are unforgettable and there are many more such examples of his childlike efforts to connect with a higher level of human awareness. His flashes of deep-hearted remorse over his horse Tub or his shy generosity to 'low-life' women he meets show his repressed sensitivity even as he is capable of fiendish acts. The book ended just as it should. An outstanding story and very gratifying read. Thank you! 

The other book is Carol Birch's novel, Jamrach's Menagerie which is part The Life of Pi, part Moby Dick - one scene of whale hunting  is excruciating - how'd she write that sitting in her study somewhere in England?!

So many wonderful books out there, we should boycott the sales figures and make an effort to search out truly good reads!  Just my opinion...