There have been a couple of recent withdrawals of web advertising recently. One was in reference to Facebook ads appearing on BNP pages. The other was revealed on a BBC programme on Childrens Fight Club where blue chip company ads were appearing on a website promote violent fights.
When it comes to advertising companies have little control over where the ads appear. Perhaps these two cases will change the way advertising will work in the future. Surely it should be possible for companies to choose not to advertise on a site?