I'm not sure about that. Maybe gambling can give profit but few days only. For long time seems difficult to happen. Winning isn't always in our hands.
I think you mean to say that gambling is not profitable in the long term - indeed I agree with you and I would also add that gambling is not profitable in the short term as well. Gambling is not meant to be a mode of earning and making profit from. It is a mode of entertainment. When it becomes an addiction then its tough for one to get over it and it leads to big losses.
I thinks those factors are very minor in place of which luck plays a major role. You can have skills and you can gain a huge experience but if you are not lucky you cant win the gamble. Gambling is about luck and it the only thing we cannot predict and then we cry about it so much.Why bother about letting your luck earn money for you while your skills went to a waste? Rather use your time and skills for some other work that will let you earn money.