Sometimes doing so is also critical to keeping your users, especially if they entrust you with something useful but dangerous.
At Loopt I think about things like this a lot, and I hope that doing so has made the service safer and harder to subvert for common questionable or evil purposes.
Simply ignoring the issues would have been negligence.
He has control over the community in the way he implements its mechanisms of interaction. Crash course here:
http://www.joelonsoftware.com/articles/BuildingCommunitieswi...
In a sense, the specific problems I raised with Reddit are just a subset of a larger issue: community-driven sites rotting at their core. Sometimes they rot at their core due to racists (and other types of bigots and hate mongers) spouting off, and sometimes they rot at their core due to idiots being idiots, and sometimes they rot at their core due to spammers.
I raised the topic because I've heard plenty of ideas on how to reduce the number/influence of idiots and spammers on community-driven sites, but I have heard far less about how to prevent hate from taking hold. This is important not just because racism and other forms of bigotry harm society, but because prominently featured prejudice-based hatred diminishes the credibility of the information a given community creates/organizes just as much as idiots and spammers do.
Our concept is not really like Reddit (or Wikipedia), and we think it is less vulnerable to the rot-inducing influences I referenced above.
Every nanosecond you worry about this is a resource permanently lost from where it belongs: your startup.
What if Henry Ford hesitated because he worried about drunk drivers? Or Edison and Bell hesitated because they worried about drug dealers and criminals? We'd still have automobiles, lights, and phones. But you would have never heard of any of them.
You have little or no control over this. Have a little faith in others; stepping forward to confront evil is their thing. In the meantime, do yours.