1) Yes and no. Yes, because that's the basis after all. No, because fairness itself is subjective too. Given the limited space, it is impossible to push every book-selling post. So I consider it reasonable to pick only some to push. Those not being push are merely "less valuable" maybe, while no one has ever denied their value in any way.
2) Yes and no too. Yes, because that's the right given to a moderator. As a moderator, the right to respond to posts based on his own idea is the basis of his authority. No, because as a good moderator, he also has to consider the overall consequence of his own actions.
Well... My point here is that there is no clear-cut right or wrong in this case. Some may consider pushing a single book-selling post inappropriate, while others may feel grateful for the highlighting of information. I would say it is better not to define this action as "right" or "wrong" in any way since there can never be a global standard that everybody agrees upon.
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