If you haven't ever used TripAdvisor, Yelp, or skimmed the reviews while shopping for products on Amazon...this article will be of no interest to you. But if you do, or better yet, if you're a business owner that is actively managing those review sites, you may want to read on.
A little background first (for those who are not in the know): If you are a current business owner, say a restaurant, landscape company or Chiropractic clinic, then you automatically have a profile on Yelp, TripAdvisor, Google+ and many other review sites out there. And the reviews your customers are posting are starting to become a more significant part of the success of your business every year.
Don't. Just Don't.
For one, it's against the policy of every review site out there. Not to even mention that it's ethically wrong. And if you're caught, the best scenario is that the fake review is taken down. From there, you could lose your listing on that review site which will immediately affect your website traffic and overall business. Worst case scenario, you and/or the personal leaving the fake review are slapped with a lawsuit.
Case in point, Amazon has filed lawsuits on more that 1,000 people in Washington who are "selling fake reviews of products", according to a story on CNN Money. These fake reviews were all sold on Fiverr.com by users creating multiple accounts. But the problem isn't just on Amazon, it's an issue all review sites have, and they actively try to manage it.
The moral of the story here is run an honest business, provide great service, and never, ever try and game the system (ie- Google, Amazon, or Review Sites). They'll be the winner every time.