I was a little confused by it at first when it happened to me. It really does seem like people accidentally review the toy rather than your review; honestly, I get fewer high votes on negative reviews than I do on positive ones.
Some people dislike it when you meld your personal experiences with the objective part of a review, so they'll vote down for that.
Other people are picky about writing style. They might vote you down if your grammar and spelling aren't perfect, or if your review is disorganized.
I also think that people are lazy about off-site reviews and, rather than click the link, read the review, and hit the "back" button, they'd rather just assume the view is "useful" so they can rate it without rating it down.
And then there are some people who wouldn't rate a review more than "useful" if their lives depended on it, even if you mentioned everything you could about the item.
Or, you know, your review could just suck and you don't want to admit it.
Honestly, that stuff happens. I think your review is really good; it's not perfect--I feel like a few facts are missing, and it's a little disorganized--but it's definitely worth at least a "useful," and I've only read a handful of perfect reviews in my entire life. Don't let it get you down!