I had written more than a few reviews for Yelp over the years, but after hearing from a couple of small business owners how Yelp was calling fairly frequently, basically offering to keep positive reviews of their businesses at the top of the default ordering for a monthly amount of money, I deleted my Yelp account and all my reviews. I felt like I was being a party to a form of extortion. I suppose it is possible TA goes after revenue in a similar fashion, but it has never come up on my radar, so to speak, and I've only written a handful of reviews for them (I no longer write any more).
One of these conversations regarding Yelp was with the owner of a small retail shop that I patronize occasionally, and he told me (and I believe him) that his business was struggling to the point where he hadn't taken a salary for 8 months. From what he described, Yelp was asking him for about $300 monthly, he told them he could not afford to pay. They responded by "filtering" positive reviews, including one of my own, and floating the negative reviews to the top of the default ordering. Basically they made the folks at this shop look like a bunch of @ssh***s, which probably helped the business to struggle even more.
While I will occasionally use Yelp to help someone find a place, with respect to the reviews, I take a little and leave a little.