If your potential employer asked you for passwords to your bank accounts, stock managers or asked you to hand over your journals, why would you comply?
I know the job market is still tough out there for people, but why would you want to work for a company that won't trust you based on your face to face interview, the documents you submit, your references and a due diligence web search?
Were people compelled to give out their AOL passwords for jobs in the 90's?
Recently, I was watching an episode of Mad Men with a friend, and one of the characters abruptly fired one of their employees. My fried was aghast and was glad that 'that behavior couldn't happen today.' Well - it can and does happen today.
Last year I worked for a start-up owned by a friend. Before coming on-board, I had agreed verbally on an equity sharing deal. I didn't put anything in writing because I trusted the guy; I knew him for years. The red flag was that he kept waiting for a certain 'favorable legislation to be enacted' before splitting up the corporation. Well, when business started picking up, I reminded him emphatically about the equity, and then I was abruptly fired. Naively, I was shocked that it could happen like that. But, every attorney I called said I was out of luck.
Anyway, the point is that employers can probably ask you to do anything they want, that isn't explicitly denied by law. So, it makes sense that they may fire you for not sharing passwords.
Either way, employers asking for a password to anything feels insanely slimy.