I would add to that that gambling in crypto sites is more dangerous than gambling in an ordinary casino.
When you bet with Bitcoin (for example) you make bets of 0,0001 BTC which seems like a small portion. However, in real money this is a decent amount. This makes gambles lose more money without noticing , so this is a risk that should be taken into consideration.
I think anything gambling is a scam either online casino or offline, this are just people that are out to get the money of innocent players by creating a platform to suck them of their hard earned money. I have lost greatly to so many online casino sites and casino houses are not left out. I dont even know which has done me more harm, whether the online or the casino houses but they are both dangerous in my own opinion.
I will only advise all intending gamblers to get a very good source of income and stop hoping on making it from gambling because it is never going to happen. If you must play at all, its advisable to do it for fun.