That wild Ask a Manager story
At a minimum, many companies will check ID before letting you enter the building.  This seems like a security risk not to do this, and NDAs are hard to enforce if the person that signed them is not the person they claimed to be, so the approach in the article of "do nothing" may not really be a good one. Checking ID at a minimum seems fine.That being said, Facebook was (as expected) particularly creepy since you need to use your real FB account for a lot of their tooling. Just by entering their (busy) lobby and without ever telling anyone who I was, they already knew my name and what I was doing.