I think that, while naming people is inappropriate and not constructive (example: grad student complaining about their supervisor Prof. Doe to be a mean, mean person), publishers are another story.
As commercial operations, they accept to be public entities and it's practical to the community to be able to discuss about a specific company (see for example this: http://academia.stackexchange.com/q/18625/10643Do Springer, IEEE, Elsevier charge a fee for non-open-access journals?), the same way we discuss the pros and cons of, say, a reference manager software. For example, there are several questions about Elsevier's editorial website (example: http://academia.stackexchange.com/q/20834/10643How can co-authors check the status of a submitted manuscript in Elsevier Editorial System?).
The same holds for universities. Why put universities under scrutiny (http://academia.stackexchange.com/q/10728/10643What is the status/reputation of the University of South Africa (UNISA)?) but not publishers?
Additionally, if a scholar is wondering about a given publisher, chances are the query will be more along the line of: http://academia.stackexchange.com/q/2513/10643Is Lambert Academic Publishing a reputable company? or http://academia.stackexchange.com/q/5466/10643Is MDPI a reputable Academic Publisher? than 'What is the process to evaluate the shadyness of a given publisher'.
There are also multiple comments and answers that are critical about the business model of established publishers and I think it's very well, but we should also be able to openly criticize the smaller, less experienced, and especially the dishonest ones.