Originally Posted by ApK
Whenever someone has a financial interest in recommending something, their motives become suspect. Salesmen who DON'T work on commission usually tout that fact because it makes people feel like they are being more honest.
This is why I disclose in a review if I received the product for free.
Affiliate links are not reviews or endorsements, though. They can be accompanied
by endorsements, but I haven't seen, say, Arcadata saying "buy this book, it's awesome". Just "hey, it's on sale here". That's not a recommendation.
And, as Catlady said, this would be fixed with a "say if the link is an affiliate one" rule instead of this "one thread to rule them all" implementation.