You know what I did when I discovered the bug in PRCDice? I reported it to Dean. He was unaware of it at the time. He had suspended betting to "investigate", found that everything was OK, and resumed betting. I sent him a PM saying that I had found the flaw and that he should suspend betting as soon as possible. Then I explained the flaw to him.

I'm not sure if he said thanks or not, but I certainly didn't get any bug bounty for telling him about the flaw. I've not seen him take responsibility for the flaw either.

That doesn't really encourage me to report the next flaw I find.

I probably will, of course, because that's how I roll (get it?), but I can totally understand people trying to exploit rigged games when they find them, especially if the site is known not to reward responsible disclosure.