Gambling is a sport and a game. But it can be used to earn money if you do it in a way that both can be seen as i telligient and responsible. It involves some skill and luck but the profits can be very high and that greatly attracts a lot of people in it. All you have to do is to always he logical and know when to play in or to fold.
My experience has taught me a little different from what you are relating here. Gambling does not offer any sort of earning. If someone is lucky, then he can get some money or may even become a millionaire but trying to use your skills or intelligence won't do any good. It is only about fate.
Exactly gambling is all about luck. You cant earn money and it would never be called as the sources of earning money. That would be a great lie and crime. Things like skill and luck both matters but in gambling weighs more than skill.
Being lucky can make your day and then life but being unlucky you can be dropped to road.