I bought some toy for a toddler. Upon receiving it, I realized that the description was misleading; many of the "pieces" they had listed boldly were just cheap plastic pieces of crap that had no useful functionality.
So I returned it, and wrote a 1-star review.
A few weeks later, I got an email from them: they were offering $30 if I took down the review. I ignored the email.
Several weeks later, another email: this time offering $40.
And so on.
Their latest email is offering me $70 to take down the review. I still haven't.
I'd forward the email to Amazon if (a) I knew they'd do something, and, more importantly, (b) I knew WHERE to send it!
Basically, Amazon has no interest in making sure that the reviews are not being gamed. Since the email goes through Amazon servers, they should be able to at least make an attempt at catching such people!