amazon sales ranks

[housenuts]

i just was looking at Caro's Book of Poker Tells and was amazed to see it was #99 on amazon.com's sales ranking.

this led me to check out the top 100. 4 poker books made the top 100.

#58 Super System 2
#86 Super System
#92 Theory of Poker
#99 Caro's Book of Poker Tells

it's interesting to see what people are buying.
my question is why does super system outsell 2+2 books? at least on amazon. is it better marketing, doyle brunson is more well known? just curious