Kids need proper training, and for a parent to teach their child properly, they don't have to gamble in the present of their child/children because children can be funny sometimes, they might collect money and gamble it online.
As a parent, if you are gambling in front of your children, then you are not responsible. Whatever you are doing, and your kids are seeing you, don’t be surprised that your kids might end up trying it behind you. You might be a gambler, and you are able to control your gambling activities, but when children start gambling, things might not really go well for them because it might lead to addiction. Just imagine your child doing bad things just to gamble, and you know they learn it from you it doesn’t really go well. How are you even going to talk to your child about gambling? Are you going to tell him gambling is bad or what? When the child knows that you are also a gambler.
So many people are hiding their gambling habits because, either they are not up to 18 years and so on.
Some people are hiding their gambling activities because they are underage, but some people are adults and they are still hiding their gambling activities. Gambling in some societies is taken as an irresponsible activity, so they don’t want people to take them as irresponsible people in the society. That’s why they choose to make their gambling activities hidden.