We can't blame gambling site that has a requirement for withdrawals, as far as I know there are some people who use gambling sites to launder their money and even without playing sometimes they just use the built in currency exchange or sometimes after they deposit, they will withdraw it immediately and of course the coins will be sent to their wallets were not the coins that they deposit as that was not how the system works.
It should be written on their terms, because if not, then that casino is a scam. Though this kind of casino is really unfair for the new, for sure it is newbie friendly because you are forced to play your deposit until you meet their requirements. For those who are heavy gamblers, this is fine because they can easily achieve those, but for those of us who are not as heavy gamblers, it is a disadvantage.