1- Would you gamble at a crypto-casino knowing it would ask you for KYC documents before withdrawal?
It will depend on what casino that is getting your KYC if a casino is well known and has established trust within the gambling community just like Stake.com then I would gladly offer my KYC, but in terms of a KYC that may not get you in any kind of trouble is good for me as well.
My opinion: No, because fiat casinos offer much better services, odds, and games so I would never want to do KYC at a crypto casino and if I was going to do it, I would rather play at a fiat casino like bet365. I don't think that's a problem for anyone so unless crypto casinos offer better services, I won't play there if KYC is required. On top of everything else, the main reason why crypto was made was to keep ourselves anonymous and if crypto casinos should follow the same path.
You can always pick an online casino that you mostly trust that you think and feel safe, and always do your own research in picking one, but if you really don't trust that then you better just play on Fiat online casino than risking your cryptos with unestablished crypto ones.
If a player cheated the casino by any means, then the casino should just ban the player because asking for KYC is not going to solve the case.
KYC is not only for the casino's safety but for the safety of your wallet aswell, but if that KYC would invade our private life and taken away your security then that is the time you will need to quit.
2- Do you feel safe giving out your KYC to online crypto-casinos?
If that certain Online Crypto casino is an established one and well known by the Bitcointalk community then I feel really safe handling out my KYC but it is always your decision to make in doing so.
My opinion: After the documents are sent, they go through a number of people and online casinos keep changing their staff from time to time and in some case, if a staff member knows my address and in case I am a high-roller I would be in some serious trouble because the staff member can track me and even blackmail me to some extent. I am ok with giving my identity to known sites like bet365 or williamhill but I am still not comfortable verifying myself at a lesser-known crypto casino.
Why would you feel that if you are not doing something wrong and something like this would certainly not often happen.