This is actually a fairly small board, ~17,000 members with anywhere from 100-400 'active' at any given time. Now take a look at somewhere like Bluelight which uses three servers and has a team of seven administrators with several moderators overlooking the some 35 forums, many of which specifically for drug discussion and even others designed for people of certain regions.
There have been reports that people arrested for drug charges have had their computers seized and analyzed by law enforcement in which certain data such as images of the convicted using drugs has been used against them in court. This certainly does not mean "they" are planning so eagerly to bust you by attempting to initiate a drug deal over the internet.
Who are the police, feds, narcs or "they" on the internet anyways? No United States government agency can persue an internet user for posting on drug-related websites, especially those who are not within the US as this is after all the World Wide Web.

If it makes you feel any better get Peer Gaurdian from methlabs.org
...unless of course they're in on it too!