Jeffrey, it is naive to think that publication cost is not a factor in the publication decision of authors from the developing world. The “traditional western journals” you referred to are quite prohibitive and while many southern researchers have published in them, many many others have been screened out by their prohibitive cost.
To me, these publishers who charge exorbitant rates (sometimes $8000 or more for a paper) are also qualified to be called predators. Or else they should let us know how much it cost them to process and publish the papers.
As for the journals on your list, i think you should be careful not to “throw the baby out with the bath water”. Some are definitely bad, but some others have well laid out editorial and assessment / review processes and are indeed well managed.
You must take your analysis further by researching the organizations further. In addition, if you really want to help your readers, do a similar compilation of non predatory “non-traditional western publishers” (i guess you must have evaluated some in the process of compiling your list of predatory ones) so that a comparative evaluation of their processes can be carried out vis – a – vis the predatory ones. You may also want to do a similar audit of the “traditional western” publishers to find out how rigorous they are in their publication process.