Holding funds on any centralized platform is a risk, not only on a casino site. Honestly, I think Betfury could draw more attention to their platform if they allowed users to receive daily dividends not only for holding BFG tokens on the platform but also for holding BFG tokens on their own addresses directly on the blockchain.
It's risky, but they haven't let us down so far... As Dwyane wrote, it's risky to hold funds on any centralized platform, but many people do it. We choose to trust the platform with our money, and in my opinion (and experience) one of the most important rules (in gambling, trading, investing...) is to hold (stake) only amounts we can afford to lose. There are many nice & trustworthy places in the crypto space, if we wish to have a full experience and try "things" we need to accept some risks.
As a gambler, I don't have a problem with that. Sometimes the risk pays off, sometimes it doesn't... that's life.