There are many examples of First Nations (or "Indian" in the U.S.) casinos doing very well, but the dirty truth about organized gambling anywhere in the world is that it's all prone to ongoing criminal activity ... which is why there are government enforcement bodies in every political jurisdiction where legal casinos are permitted by law to operate.
But just like simply having a police department doesn't in and of itself stop crime, having a government gambling enforcement body doesn't stop all money laundering, loan sharking, etc, etc.
Crime and legal casinos go hand in hand in 2019, as they have always gone hand in hand, but the Federal and Provincial governments continue to license casinos on the premise that (like police departments do for society in general) they are doing their best to enforce laws as they relate to legal gambling, and to create opportunities for law abiding citizens to gamble in a comfortable and secure environment if they so choose to.
Any casino executive, law enforcement officer, government inspector, or politician claiming the possibility of a 100% honest bricks and mortar casino operation is, quite simply, an outright liar.