When someone posts a question to a midrange.com mailing list, there is often a 3rd party product that will directly address the issue.
Vendors are allowed, in fact encouraged, to reply to the question and describe how their product DIRECTLY addresses the issue.
When doing so, vendors should make it clear that they are a vendor. If a vendor representative post a message where it is not clear who they are representing will be given a single warning. After that warning, a subsequent violation will result in removal from all mailing lists.