You cannot assume that any filtering is being done unless they explicitly say it.
Also, I generally dislike the idea of excluding any sort of address from mixers in the first place. You can think about it for a second with a simple example. I'm sure you know that there are a lot of BTC users in Iran or Venezuela for example. So what happens when a bunch of Bitcoin addresses belonging to these people are blacklisted for "money laundering" although it is a blanket ban?
The problem here is that we do not know the honesty of the people who make the rules about this.
Got your point. I will be more careful next time with my words, explicitly. I also don't like the idea of excluding addresses from using a mixer because then what purpose it will have?
A good mixer cannot require kyc or do anything to deanonymize their customers, that would defeat the purpose why one wants to use a mixer, which is for privacy and anonymity. I also do not believe in the 'dirty' BTC bullshit, neither do i agree that coins should be blackilisted, because that is an attack on BTC fungibility. RoyalMix service has not said anything about blacklisting addresses, so let us not speculate on that.
I also tried to say the same thing, that KYC can't be taken via mixer because that's not their purpose. I did not know about the thoughts of you guys on dirty BTC but I am glad now I know.
They are not obtaining KYC and other stuff to prevent Money Laundering. So this must be it. If you want to share something on this then I'm all ears.
Why on earth would any mixer ask for KYC from their customers and why would they try to prevent anything? 
RoyalMix is just a website that is offering a service to help users conceal their past transaction and provide more privacy.
I also tried to say the same thing.
You seem like you don't understand the basic concept of a mixer. AML check and mixer service does not go together at all because one cancels the purpose of the other.
I know mixers should not be asking around for our IDs and that's what their purpose is. And that's not what I meant. I said they can't ask for IDs then they might be using this method for blocking purposes, but I never said they wrote it somewhere, I thought it was the easiest way to make it happen so I put maybe. I was unable to convey my point.
They are not obtaining KYC and other stuff to prevent Money Laundering. So this must be it. If you want to share something on this then I'm all ears.
Money laundering is what the address owner is trying to do with the mixer, and it doesn't actually change the fact that the next addresses tracked will be blacklisted as well. Don't think that services that implement KYC are not exploited by criminals. CZ was arrested for money laundering on his centralized service. Asking for kyc only hurts normal users who want privacy. The mixer business doesn't work this way.
I have a good knowledge that, KYC can't really stop money laundering because people are so smart that they can bypass such verification systems too. I also know mixers aren't supposed to ask for verification. I think I was unable to convey my point. Sorry for that.