Here is my own "take" on people who just sign up to remark on a review.  I have had several of these.  Sometimes they either hate us or want to date us!  At any rate, they only seem to do this when they are feeling emotionally charged about something we have written.  My guess is that many of these people are connected with the companies that make the products we have reviewed.

Sometimes you have to love getting these as some people who sign up (i.e., TheSoupGuy) are very nice.  

Alas, I have gotten some that were really nasty too.  One person was so hostile that I actually broke out in hives when I read their message (an unfortunate thing that seems to happen to me now and then in stressful moments, nobody is sure why). 

That's the last time I'm going to break out in hives because someone doesn't like a review though because from now on, I figure if somebody has taken the time to sign on just to remark on a review, then we should consider that review a success whether the remark is positive or negative.  Either way, we have rung a bell and someone cares what we have said and that's the most important thing.  Nobody ever promised any of us that everybody would cheer for whatever we have to say. 

Take care everybody!