At the moment, responses are being fair to both you and the casino based on the reserved right to request in the ToS. If it was not stated explicitly there on the ToS then manipulation could be going on the minds of people.

Centralized casinos have a way of trying to beat customers to their game. Unfortunately, I think legally such clause of reserved right may over ride .

Have you read the full TOS? If not, then maybe you should review it. Sometimes, sites' marketing strategies are deceiving just to attract gamblers, but it's already listed on their TOS. So, it's wise to review all that stuff so you know when to complain.

8 mbtc could be a lot of money, if you can comply with the KYC, then maybe just comply to withdraw the funds. Now, if they still don't release your funds after you complied, then we can conclude that the site is scam.

without a doubt that the behavior of this casino is not ethical, they have no word, from the moment they write that in their casino they do not need to ask for KYC for crypto deposits and in their TOS they talk about KYC for everyone so we are facing a casino Liar, they said they wouldn't ask for KYC for crypto deposits just to attract people who love privacy, they lied. although that doesn't make them a complete scam because they still have their TOS that you agreed to when you agreed to use their casino. researching more about this casino I could see here:

https://www.trustpilot.com/review/justbit.io

there are many accusations of scam, looking at the number and style of comments i believe it could be comments from many people which would show that this casino may be providing shady services, my advice is that you do the KYC and then withdraw all your money and never again use the casino or else you should post your case here:

https://casino.guru/justbit-casino-review#tab=js-tab-reviews

I believe that when posting on casino.guru they will look and resolve your case because from what I see they care about having a good reputation on casino.guro

Back to the same case where gamblers complained because the casino declared non-KYC, but when there was a big win and the money was withdrawn, the casino asked the conditions for withdrawing the money.
It's better to ask their support first if there is a large withdrawal or not KYC because there are several casinos that have cases like this, friend.
In the future, you should always find out important information in withdrawal transactions in advance so that problems like the one you are experiencing don't happen in the future.
I'm not saying the casino that you say is bad or a fraud, but it's better to fulfill these requirements and withdraw all your money then look for another casino that is more popular and trusted, friend.

Any centralized and regulated service platform may ask for KYC at any time even though there isn't mandatory KYC policy but with the site you mentioned they clearly stated that before withdrawal of funds the user needs to pass KYC so its you negligence towards their terms which costs you 8mbtc but you can withdraw the funds once you complete the KYC and whatever they ask so this isn't a sign of scam but make sure you didn't fall for fake website.

This is for all gamblers if you don't want to have future issues with your session and your withdrawal read the casino TOS and always get an update if there are changes in their TOS, don't just believe what other people are saying or what's showing on chat or homepage, the TOS is your guide on all your action in a casino that you're playing, this is another case of not reading the TOS, and believing that there are casinos with no KYC.
Justbit should take down on the images that state that they have no KYC for Crypto players because its misleading and they have a victim here.

Some casinos are posting a no KYC on their advertisement just to attract more players which is actually unfair to those who seek KYC free casinos. I think the only thing that we can do so we won't feel upset is just to expect that casinos could probably ask for KYC on their own prerogative. Most casinos that announce or advertise that they won't ask for KYC usually requires it upon withdrawal which is very disappointing so we better be ready for KYCs all the time.

Sounds like when you were going through the terms and conditions of the casino before you started gambling there, you only searched for terms and conditions regarding some key details like KYC verification and did not take time to read through the whole thing. You did good even trying to read the KYC in the first place, but you will do better just as everyone else here if you read the whole thing. That I know can be stressful, but it is advisable because only then will you get the whole scope of the terms and conditions and know if you will still play there or not.

I am a strong opponent of identity verification when it comes to gambling with cryptocurrencies. 
Because KYC with cryptocurrency payments is just a mockery of common sense and the very idea of ​​anonymity of cryptocurrency payments.  Bitcoin itself was invented by Satoshi to preserve the anonymity of payments. 
This is the main meaning and advantages of cryptocurrencies!!! 

Here is another example, when, in general, the casino will simply not pay a large amount of money to the player if he does not tell exactly who he is and where he lives.  And he will give his personal personal data.  In these dirty tricks that casinos constantly do, apparently there is a lot of sense for them.  After all, the money will not be partially returned to those who do not want or even simply cannot go through KYC for their own reasons.  Sometimes it's not even safe for the player or can cause serious trouble. 

I'm sorry, but I must admit that now "sudden KYC" is always to be expected even from any casino. 
Alas!  All of them are afraid to break the laws, which are becoming tougher in relation to the population. 
And on the control of finances in the first place.

Do not easily get taken away by that phrase. It has been used by different casinos, but most of them still ask some of their users to process KYC. It could be there were suspicious found related to your account or they are those that are suspicious. Or with a neutral reason, probably this is a misunderstanding.