I'm just guessing, but:
http://scitech.blogs.cnn.com/2009/06/19/want-a-job-hand-over...
http://scitech.blogs.cnn.com/2009/06/19/want-a-job-hand-over...
My take on the situation though after reading the article is just a case of understandable incompetence. They just didn't realize what a big deal it was. They were looking for a limited number of bad flags and didn't really think it through. Someone with very little social networking experience, read some nightmare accounts in some FUD article and made a really dumb decision.