I believe it. I work in the insurance defense industry as an fraud investigations manager. We've found claimants for worker's comp back injuries posting pictures of their weightlifting competitions, people posting pictures of their car accidents during times when their policies lapsed (then reporting the accident and filing claims after they reinstated their policies). Social media is a gold mine.
During the 2009 recession, I was given the opportunity to find a new job. After flying out for an interview, I came home and told my family the interview went well and was expecting an offer.
My then teenage daughter immediately posted it to facebook. She got upset when I told her to delete it.
I told her that I had no idea how sophisticated the company was about doing background on prospective employees and I didn’t want them to see that post somehow.
(In retrospect, they weren’t nearly that sophisticate and I did get the job)