This is a question I've pondered.  The provider often has detailed information about you--where you work, and possibly live, your phone numbers etc.  So you have a lousy experience and want to let your fellow hobbiests know about it.  Aren't you a little afraid that they might take revenge?  You hurting and in some cases killing their business?  The power is in their hands--you only thing you know about them is their fake name and not much more.