That site isn't illegal, nor are passwords being exploited or is there any chance this could be used to hack the site.
The reason for a password being posted on that site is simple, some people don't see the need to register to view content (like patches and attached images), as registering takes more time than just going to that site, putting the name in and then getting a username and password. It just saves them time, and for the majority of people there is nothing malicious.
The passwords on that site exist because someone who made an account here decided to post those details on the site themselves, no one's passwords here were hacked by anyone and there is no need to panic. This isn't serious and your account is safe. Though changing your password regularly is a good idea nevertheless.
I personally don't care if someone uses an account like that to view this site, provided they don't post with it or use it to hide their identity, it doesn't hurt anyone.
I'd also suggest people read their terms and conditions before they make a fool out of themselves by complaining about the site to the host or directly to them, you are just wasting your time.
. I have reported abuse to the host of that site.
