I presume you've been there and witnessed this mass murder, torture, and famine first-hand? I also presume you can account for never having spent a single cent on any product that may have originated in North Korea (let's point out here that Korea trades a lot with China and China exports a fair amount to other countries...). I'd like to further presume that you can account for the North Korean government not spending a single cent earned from tourism on supporting the health, education, and general welfare of any of its citizens - normal every day people with jobs and families and interests? If I may make 1 more presumption - the government to which you may pay tax, as well as those to which you've ever contributed to via tourism, trade, or other means, have never spent any money whatsoever on anything that might be deemed unacceptable according to the current Western moral zeitgeist? How does China tourism fare with you? How about Saudi Arabia? Ever paid for anything from either of those countries?
While some tourism money obviously does go to into government programmes that most of us are going to disagree with, I don't think that's an argument against North Korean tourism altogether. Such programmes would likely continue with or without tourism money.
An agency offering North Korea tourism packages is not only serving a market demand (are you claiming that anyone who is interested in visiting North Korea is "disgusting"?!) but also offering an opportunity for increased understanding. There is value in what they're offering, to both North Korean people (not just their authoritarian government) and the people who visit.