• by Gavin O'Malley , Staff Writer @mp_gavin, June 9, 2015

Benign as it may seem, Facebook Login is actually “the embodiment of evil,” according to Dave Hendricks, President of email ad server LiveIntent. “You don’t want to use it,” he told those in attendance for MediaPost’s Email Insider Summit, on Tuesday.

Positioned as a quick and simple way to sign in to new online services, Login allows third-party sites to authorize users using Facebook infrastructure. By taking this shortcut, however, consumers (unwittingly in most cases) surrender their data to Facebook, which is then free to manipulate and monetize it pretty much any way it likes, according to Hendricks.

By Facebook's count, more than 80% of the top 100 grossing apps in the U.S. use a Facebook login. And, it's no surprise why. A whopping 92% of consumers report abandoning sites after forgetting their username or password, according to Janrain. Marketers, however, have to weigh the many pluses and minuses of allowing users to sign in via Facebook and other social servies.