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, the same way we discuss the pros and cons of, say, a reference manager software. For example, there are several question about the online editorial website of Elsevier. 

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/2513/10643 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 nominatively criticize the smaller, less experienced, and especially the dishonest ones.