Is it illegal to write an ebook like amazon ghost, amazon stealth or amazon suspension guide?

I know that Amazon suspends a lot of their sellers often & mostly without morals. I came across 3 eBooks that may be purchased where you can learn how to open another Amazon Seller account. My question is: is it legal for the writers to sell these types of books? Even if the books contain nothing illegal in themselves, will their selling of their books ever come back to bite them?
Can Amazon sue them for writing these books?
The Ultimate Amazon Suspension Guide
Asked Aug 07, 2013
Your blog will be banned.
Answered May 26, 2016
Amazon Affiliate Income Guide 2017
Answered Nov 07, 2017

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