While I can understand your concern, let's look at a few things. 1 are you going to pay the costs to maintain a database with user's credit card information? I mean it should probably be PCI compliant right? That's not really cheap. 2 Are you going to be able to provide some guarantee that this information will not be abused? Plus the moderation team does it's job with generally little thanks and certainly no pay. So I doubt they want to have some additional burden placed on top. Considering that they have families, jobs, and the like.
Further let's be a bit more realistic here, there are an uncountable number of websites, forums, blogs, etc. that contain the same and more information that could be used for nefarious purposes. Now while the moderation staff does it's best to insure that no illegal activities take place here on the forums, we can never guarantee that any information gained from here will not be used for such. Having said that we can not be held responsible for how individuals use any and or all information they get here. Further would you really trust a website that also hosts the number one penetration testing distribution with your credit card info?
That alone should probably convince you. If not think about the number of little kiddies that daily try to attack this site.