Besides this, I do not want to advise anything to adult players, but the basic concepts of politeness and respect for an unknown interlocutor should be observed, at least I try to do this.
The thing is one should give advice if the person is seeking advice. Even with suggestion, it should be given with the consent of the listener especially when they are asking for it. If they don't ask for anything then we should keep our mouths shut since they don't want any advice or suggestions.
Some people can't just mind their business as they always want to intrude in people's affairs even when the listener doesn't want such attention. People should learn how not to force themselves to conversations that the listener is not interested in
If we get ahead of ourselves and give unsolicited advice, we might find ourselves in trouble because people might find it annoying or offensive. Like when we meet someone who is into gambling and give him unsolicited advise that gambling will ruin his life, instead of making a good impression that we care, these people might think we are stepping over our boundaries.
Except a gambler meets someone for help they rather not give unconsented advise because they can get into trouble just like you said, I have seen someone losing heavily in gambling and someone besides him just told him he's wasting his money that he should instead quit instead of continuous losses, the gambler became angry and it led to a rift between him and the person advising him to quit playing and he was asking the person if he was gambling with the person's money. If anyone should give advice to a gambler who is running into numerous losses let it be that the gambler actually approached them for advice.