Casinos that issue their own tokens will get funding from token sales to develop their casinos bigger
I don't think they used those tokens to raise funding but in order to get those tokens you need to mine it via wagering. Thats whales wager alot during the opening of the casino because the mining difficulty is too low because if the level of difficulty increases the wager requirement also increases and the rewards decreases.
Maybe you are referring to BetFury? But most casinos that created their own tokens are for funding or additional sort of purposes. Moonbet for example is for funding purposes. Not sure about OWL. I remember some years ago when I was invited by a friend here to check Betking's crowdfunding in exchange for their tokens that are guaranteed future dividends when the casino starts earning. During ICO days I saw a lot of casino projects here marketing their tokens in order to start their businesses. Most failed I guess as I haven't heard them now.