While I agree with the idea that you should never share your password, you're blaming the victim. Having read a few accounts of their exploits now, this company is manipulating these people.
Some victims deserve blame. It's the rare con job that plays on our virtues and wisdom rather than our stupidity and baser desires.
So they deserve what they got for wanting to see pictures posted by their friends?
I don't think it rises to that level, but tedunangst and gojomo are both right in that imprudent user behavior was a necessary condition of this happening.