gambling is often seen as a harmful habit. my question to you is, in a completely free society, should someone be prevented from providing gambling services for the good of society?
When money is involved, things take a toll on the psychological state of a human mind. Gambling is not a bad thing when one takes it as a form of entertainment rather than an occupation or a way to get rich.
The fact that it affects one's mental state, it can lead to scenarios like suicidal thoughts. I guess this is why some societies demonize it but if you know what you are getting into, you will barely get affected.