And, as far as the patent buying goes, I don't really see a moral hazard with arbitrage. Either the market for patents is really inefficient and they're reaping rewards for exploiting that, or they're actually (gasp) providing a service to the market by connecting companies to institutions, and they're being compensated for it. Either way, I'm thumbs up on the enterprise.
Doing pure research isn't making an honest living?
After all, if one can't make money off of a thing purchased from a professor, there's no reason to buy said thing from a professor. Is it wrong for professors to make money from what they invent? In many cases, the school also makes money. Is that wrong?
Or, is it just wrong for middlemen to buy and resell? In other words, professors should only license to end users.
Note that you've already excluded "publish your invention and charge other people to use it".
They are extortionists and vultures. Their business model is to buy cheap patents from people who just do pure research. Then they go and sue the pants off people who do real work and make a honest living by doing things that make real products.
So I don't know how you can say they need to be proven guilty when they plainly state what they are doing.