Re: They know the truth but they don't want to accept it, publicly
It depends on how to treat gambling, people gamble because they want to have fun's gambling real purpose is, to give entertainment to the players, but few of them treat gambling as one of the possible sources of income because in just a single game you can hit a hundred or thousand multiplier that's why they take it more seriously, but if you are just a casual gambler want to have fun without having the bet i guess still ideal to you to play a game without money involve just pure fun. Money is just additional to make the game more spicy.
It's no longer a gambling if money isn't involved. 
When people get older, they prefer to not wasting their times, if they only predict without earn anything, it's no longer fun anymore. That's why matured people are often gamble, even it's as low as a candy lol.
As long as they gamble without exceed their limits, they will be fine.