There have been a number of such initiatives. So far, I have seen no evidence that any sex trafficking has been surfaced by them.

The only result, always, is arrest of sex workers who in the US of course face criminal prosecution.

When you read about dozens of arrests in a big sex trafficking investigation, it is always woman who are being arrested, and on occasion clients.

https://www.google.com/amp/s/deadspin.com/when-the-robert-kr...