Why do the ritors ask for Justice?

[Athene]

Protesters are seeking justice. 

Rioters are probably not. They're opportunists for the most part; plain and simple. 
Their primary interests are their own.

People just can't be bothered to acknowledge the distinction between the two, I guess.

I'm sorry did I say protesters were the same as rioters?

My thread is focused on those who use 'justice' as a way to excuse criminal behavior.

No vengence= We are allowed to burn down businesses, loot stores, kill cops, and the like.

No, you didn't say that.

But, it's clear to almost anyone, that rioters  who engage in burning, looting, and shooting at cops have an ulterior motive; Doing what they like, because they can. 
That's not exactly a revelation.

So, I assumed the OP may have been addressing this "race-based group" as a whole.