Comment by powercf

The car analogy would be:

  He saw a car
  He tried the doors until he found one that was open
  He climbed in and searched everywhere until he found personal information about other users of the system

Even though the security of this system was poor, he still (probably) broke the law. There are plenty of opportunities for people with some knowledge of IT to abuse their power, but it's our responsibility not to do so.