We've all looked at reviews online. I actually find them entertaining. Some sites really do have some over the top reviews where an inconsequential widget like a can opener is shown to be the end all of all creation.
Those are usually very easy to spot. You will hear about an item on an auction site that has taken a life of its own and frustrated comic writers try to sharpen their wit and see if they get any attention for it.
That is rather harmless, kind of a prank. A recent one was the three wolf moon T Shirt review on Amazon where putting on the T Shirt has been said to cause the wearer to get the powers of levitation and control over a pack of wolves, specifically in a Wal Mart. This one has been going on for a couple years now as an established Meme.
But that isn't astroturfing. Astroturfing is the practice of posting fake reviews by someone connected with the company or product in order to drive sales or traffic to the site. They're usually pretty easy to spot, and pretty easy to avoid. When you hit a review site like Yelp, simply skip all the Five Star Reviews. They're usually written by some second cousin of the owner of the shop anyway.
I've spotted them in company reviews posted on Glassdoor. Glassdoor is a site that exists to allow people to research a company they are interested in working for. Hopefully they will give a glimpse inside the Glass Door to allow them to decide whether the company is worth applying to. I have seen some reviews on Glassdoor that were clearly written by the owner, and they're always "called out". What generally happens is that someone who was working there will post an anonymous review stating just how awful the company is and how it is mean to puppies and kittens and ... well you get the picture.
But Astroturfing also has a darker side, and luckily we have New York to thank for spotting it. There's a practice called "Search Engine Optimization" where a website is written in such a way to raise its ranking on a search engine. The current wry definition of frustration is the act of proceeding to the second page of a web search in order to find something about something you need. So webmasters, myself included, will try to add helpful links and comments in the page in order to make it more important and more pertinent to the web search engine. The problem is that the rules are never told to the webmasters and they change all the time.
Search Engine Optimization is usually a guess. A "Scientific wild-assed guess" or a SWAG, but a guess.
So what happened in the case of New York is that the State created some yogurt shops and looked for help in getting their pages optimized. The shops never existed. Some companies were valid and helped the shop "owners" work their webpages over with some commonly accepted techniques. Others were more devious and resorted to Astroturfing. These companies offered to have fake reviews posted in Yelp and others to drive traffic to the site. That isn't exactly legal as it deceives the potential client by having people in places like the Philippines and others posting these glowing reviews of a shop that they never visited and doesn't even exist.
It's also apparently illegal in New York, and should be illegal everywhere else.
Luckily these reviews are usually easy to spot, and normally easy to avoid. Just avoid your Three Wolf Moon T Shirt. It's out of fashion now and worn "ironically" just like the reviews.