No!!! Gambling is a sin only for those who does not know the techniques and tactics of gambling. Gambling is a form of art if you are betting in sports or something technical. In such cases it will be proven as easy money earner.
i think you're wrong about this because we all was know that almost in all religions decide gambling is a sin and they will says just stay away from gambling but the problem is even people already know about that but many people still did a gambling for a hobbies or for fun and even too for make living