I think keeping your activities as a gambler a secret is also a positive thing when you try to keep it a secret because in this case the treatment or view of each person to gamblers is a little different. I don't know about other countries but in the country I live in, especially in the area I live in, the stigma of "gambler" is seen as someone who has a bad habit and is viewed differently.
Even though there is no prohibition for us to gamble because it is the right of each person but still the view will be bad so that when we say clearly that we are a gambler then surely we will be labelled as a bad person.
For some people it may not be a problem and tend to ignore people's judgement but for others of course it is very disturbing so it is better to keep it secret than we end up being seen differently.
Gambling is something that has natural forces whereby you may not know when to showcase yourself as a gambler but whenever the discussion are being carried out by friends you don't know when you would join the discussion freely and exposed yourself as a gambler. One thing about gamblers they are not always hidden no matter any circumstances you still can reveal yourself without knowing you had already did, what just matters is that we should only be mindful with the way we discussed with friends especially when A knows about your gambling nature it's very easy for B go know you gambles because it could be leaked by A that you are a gambler. So what I am trying to say is that it's very difficult to remain unrevealed about your gambling habit hence you are much more at risk of being exposed to people out there all less don't associates with friends and relatives.
I think by looking at the statement you made, it indirectly suggests that it depends on the situation whether we will hide our identity or admit directly that we are a gambler. I agree with this because when we discuss with a friend who is a gambler then I don't think we need to cover ourselves that we are also a gambling player but on the other hand when we talk to people who are not gamblers then we should not admit that we are a gambler because surely the judgement will be different.