it all depends on the knowledge they have, if as a beginner it is easier for them to play casino, then you should use the casino as the first place to gamble. but for me, I prefer sports
We must remember that gambling is supposed to be done for fun so even if there is a more profitable option, or at least one in which you could reduce the amount of money that you lose, all of that is for nothing if you are not obtaining some kind of fun out of gambling.
Which is why if people want to play traditional gambling games like dice, roulette or blackjack then they should be free to do so, and they should only concentrate on sport bets if they actually like to watch sport competitions, otherwise they are just wasting their time by doing something they do not enjoy.