Caedes, I see where you are coming from but I think there is a big difference. Many thousands of JWs lives have been severely affected by spending their formative years being described as 'spiritually weak', 'easily lead', 'bad association', 'not humble', 'worldly' etc etc just for having the audacity to think for themselves and not be a robot like the rest of the JWs.
To call the Society 'WashTowl' or indeed far more derogatory terms, is not aimed at anyone personally, or used over and over again by members of their own congregation to mentally break them down in what can only be described as mental and emotional bullying.
You may feel it is hypocritical to use such insulting terms to describe the WTS but the difference is that it is not going to affect anyone as individuals or destroy their confidence, lead to depression and damage their ability to form relationships in their adult lives.