Here's the top half of a banner ad for the latest edition of Diplomacy that I just spotted on BoardGameGeek. It's unclear whether this was designed by the BGG folks, or by Avalon Hill / Hasbro themselves, though there's no reason to think it isn't the latter case.
Even if that's so, I'm guessing it's a custom-produced ad for BGG, a very popular site with a huge slate of semi-apocryphal group-knowledge; all BGG fans know that Diplomacy's a great game that you should never play with anyone you care about. Even so, "buy this game because it will make you sad and alone" still seems an odd message to make so overt in your ad copy. It'd be like seeing an ad for Fluxx on BGG using the site's general attitude about that title: "Everyone in the world hates this game! How the hell have we sold almost 400,000 copies! Get yours today!"