Invest only in gambling sites with perfect reputation.
Yeah after the recent Cs Go gambling site scandals the same could be the case in bitcoin casinos. Owner of these sites could just play themselfes to take money out of the sites and all investors would need to cover it.
Just make sure the site is actively used before investing it.
Yeah, not only gambling sites, also different sites are fake, so i suggest whenever we want to invest so firstly you should have the satisfaction about sites than invest it, i never say that all sites are fake but mostly are fake and some sites are really good sites and they are giving very good paying. But in gambling, i think more opportunities are here to earn the profit.
Sometimes, it can be even harder to find out HYIP's; some cloud mining sites are actually HYIP's in disguise. I think with Bitcoin, investing in gambling sites is the safest as you know what your money is going to go towards, and many people invest so you can ask people questions. However, if you start losing your investment in a gambling site, don't panic and withdraw unless the site is going through some serious trouble, as you'll usually make it back on the long run.