You're free to do whatever you want and like in this world, provided that it doesn't harm you or others. If, in your opinion gambling isn't harm, yes means not wrong. Vice versa.
But we are not really free, there are still some restrictions that keep us from doing what we want and love. In this world, we are restricted by many things, family, even our culture and religion, and we will do things to make it happen, to do what we want, even if we need to hurt or harm others. But it differs on how we put an opinion to something, and how we treat them, so when you treat gambling as a mere entertainment, you are doing great.