A couple of points on this, Evilized. First, Sun isn't the only person to complain. Second, you have acknowledged that Bundle Bandits leaked users' email addresses. This is not only incredibly bad form, but can lead to an account being hacked, and in this case, the timing would imply that it did. This wasn't a minor error. This was a serious failure, regardless of how directly it lead to an account hacking (though common sense would imply that it was directly responsible).
That leads to the third and fourth points, which are substantially more problematic. The third being your handling of the situation. First, Sun's email address was leaked due to the terrible practices of a company (Bundle Bandits). Next, Sun complains about this fact. Then (and this is the big one), you proceed to tell him that it "Might be your attitude towards others online that made someone angry and do these thing". Really? Did you just openly state that he "deserved it" because you feel he was being rude online? The perceived rudeness seems justified, but even if it wasn't it seems like a terrible PR move for you to acknowledge an error that compromised someone's email address then tell the customer that he deserved it. That is inexcusable, and no way to treat a customer.
The final point here follows directly from that; you joined this community to advertise your product, then proceeded to attack an active, valuable, and respected member of said community (by implying that there are problems with how he conducts himself or treats people online). Your actions in these forums directly influence how this community will perceive you, and therefore your product. I don't think irreparable harm has been done, but I'm not sure it's the message I'd want to be sending out.
Like Fox, I picked up your game through Groupees. It looked interesting, and though after this thread, I don't think I'll be playing it, I do wish you the best. I want you to succeed, truly. I think joining this community is an excellent way to get the word out, and promote your product. As mentioned previously, Sun is a respected and established CAG. My personal recommendation, then, is to avoid harsh criticisms of your customers, particularly in communities in which they are valued. That's not the kind of publicity you need.
Best of luck.