I agree with you. Both activities are similar in some aspects. In both you need to predict the results of the market or of the numbers, in both you can make a lot of profit and become rich, in both you can work at home on internet.
I prefer gambling, because I know how to do it better, but I know trading is profitable too and many forum members are earning money this way.
I am agree with your first point, that both have similarity because doing the trading and playing the gambling have a same way, we can judge it and do it.
But i am disagree with your second point that both are profitable ways for many time, I accept it trading can be profitable but it need long time, it is hard we earn profit on everyday. And secondly, gambling can't be a profitable and help us to become rich, because i have play gambling since last 2 years, but still i can't see anyone who become rich from only behalf of gambling.