I felt an overwhelming need to post this in response to the OP's question.
But in all seriousness I think it boils down to the following;
1. There is no,either real or perceived, social contract of responsibility. Behaving badly still gets the same reward as being an exemplar of social etiquette.
2. Sadly Blizzard's current implemented design of VTK, while it has come a long way, still isn't sufficient. And people know and abuse it.
3. LFR since the inception has been called "easy-mode" and "training wheels". And when a mechanic proves to be difficult its only a matter of time till Blizzard either nerfs or removes it entirely. And people have gotten used to queuing for LFR and anticipating that paradigm will prove true time and time again.
4. Trolls will be trolls. And people will be people. The internet is the single greatest reflection of the depravity and cruelty of humanity.