I have recently signed up in a new casino and I'm receiving some bonuses with the wagering requirements we are discussing in this thread. The thing is that I have always thought that very high wagering requirements are abusive, but taking into account that the bonuses I'm receiving aren't linked to any deposit I make, I suppose that it is fair for that "free money" to be used as "test coins" and only be able to withdraw for real money after a very lucky strike. In the meantime, the player gets fun and used to the casino at the same time.
In most cases, you can't expect the casinos not to be that wise enough that you signed up and received their bonus and uses that same bonus to gamble and win and expect them to allow tou withdraw the whole money, things aren't done that way and they may not agree to that terms, you must also show commitment in making at aleast some deposit to use for gambling before making withdrawal, some casinos would have alert you on this before time while some will only tell you when you needed their attention to perform some functions from which are being denied.