You can become rich from gambling, but you need to have a great luck.I have seen some users which make a great win by gambling from time to time from dice, sportsbet and even poker.
Yes we can ,You can ,be rich if we earn one big time income or continuously big win amounts., i think it doesn't needs luck when gambling it is only our state of mind that pushing us.
Sports betting is a prediction game so its requires good prediction ,poker games requires stratedgy and skill to play on.
you are right, usually these 2 are easier to make money cause they requires skills instead of just pure luck. So if you are really good, you can really make a living out of it.