High Risk Merchant account question

I am a newbie learning up on High Risk Merchant accounts and I read this thread that had one member complaining that the High Risk Merchant account companies are mostly middle men or 3rd parties that get their money and run, leaving the Merchant high and dry.

Can someone who knows this space explain what he means? Who are these middle men, 3rd party or reps who sometimes "rip off" merchants? This stuff is still very new for me.

If they are not listed on these, you may want to keep your distance from them:

http://www.visaeurope.com/media/images/pci_dss-73-17813.pdf

http://www.visa.com/splisting/searchGrsp.do